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Windows XP

A typical Windows XP .
A typical Windows XP desktop.

Windows XP (codename Whistler, also known as Windows NT 5.1) is the latest desktop version of the Microsoft Windows operating system. It was made publicly available on October 25, 2001. Two editions of Windows XP are most commonly available: Windows XP Home Edition which is targeted at home users and Windows XP Professional which has additional features such as dual-processor support and the ability to join a domain, a grouping of centrally managed Windows computers. The letters "XP" originate from the word "Experience". [1]

Windows XP has brought to the consumer line of Windows new features not available before, such as stronger stability and efficiency due to its pure 32-bit kernel instead of the hybrid 16-bit/32-bit in consumer versions of Windows before it. In addition, there is now support for new hardware. A work-around has also been devised for the DLL hell that plagued older consumer versions of Windows due to inefficient software management. There is also a new look for the graphical user interface (GUI) that Microsoft promotes as more user-friendly than the older versions of Windows.

Windows XP has had many security issues; as of February 2005, there have been two service packs released to address security problems with Windows XP. Windows XP has also been the first consumer version of Windows to use product activation to combat software piracy, and this restriction did not sit well with some privacy activists, and indeed many home users. Spyware and adware are a continuing problem on Windows XP and other versions of Windows. These usually unwanted programs can cause system instability, display advertisements, and track a user's activities for marketing purposes. Often these programs are included with seemingly harmless downloads. Spyware is also a concern for Microsoft with regards to service pack updates.



Before Windows XP, Microsoft had sold two separate lines of operating systems. Windows 95, Windows 98, and Windows Me were designed for home desktop computers but did not have reliable memory protection, while Windows NT 4.0 and Windows 2000 were aimed at the corporate, professional, and server markets but were less well-supported by game and multimedia developers. Windows XP (Windows NT version 5.1) is an evolution of Windows 2000 (Windows NT 5.0) with additional features for home users; it represents Microsoft's shift to using a single code base for all its operating system products.

Windows XP's Service Pack 2 improves on XP's integrated software firewall and introduces a new Security Center to monitor firewall, antivirus and updates. It is part of a major new Microsoft security effort following a long history of security issues and vulnerabilities. Unfortunately, it is still not infallible and some users object to the new restrictions on functionality placed on Internet Explorer in order to improve security.


Microsoft released two main editions of Windows XP. Windows XP Home Edition is designed for home users, and Windows XP Professional is designed for business use.

These are prominent differences between the two editions:

  • Windows XP Home Edition cannot become part of a Windows Server domain, a group of computers which are remotely managed by one or more central servers. Most businesses that use Windows have a Windows Server and a domain.
  • Windows XP Home Edition uses by default a simplified access control scheme which doesn't allow specific permissions on files to be granted to specific users under normal circumstances. This can be accomplished while the operating system is in safe mode, a troubleshooting feature of Windows.

These features are present in Windows XP Professional but absent in Windows XP Home Edition:

  • Remote Desktop, software which lets users control a PC over the Internet.
  • Offline Files and Folders allows a PC to automatically store a copy of files from another networked computer and work with these files while disconnected from the network.
  • Encrypting File System encrypts files stored on the computer's hard drive so they cannot be read by another user.
  • Centralized administration features, including Group Policies, Automatic Software Installation and Maintenance, Roaming User Profiles, and Remote Installation Service (RIS).
  • Clone Display allows users to "clone" their monitor onto a secondary display (a feature often used in video production). While it does support video cards with dual displays, XP Home limits this feature only to extension of the primary display, and not cloning.

New and updated features

Windows XP introduced several new features to the Windows operating system line. Many of these had been intended for Windows Me (which was originally designed with the idea of combining a new user-friendly interface with the Windows 2000 kernel), but due to Windows Me's rushed release, were put off until the release of Windows XP.

Improved device support

Windows XP provided new and/or improved drivers and user interfaces for devices compared to Windows Me and 98.

Windows Image Acquisition (WIA) replaced the traditional TWAIN support for scanners and digital cameras. [2] [3] As TWAIN does not separate the user-interface from the driver of a device, it is difficult to provide transparent network access; whenever an application loads a TWAIN driver it is completely unattachable from the supplied manufacturer's GUI.

Still Image (STI) support is provided as a compatibility layer within the WIA subsystem.

On old versions of Windows, when users upgraded a device driver, there was a chance the new driver would be less efficient or functional than the original. Reinstalling the old driver could be a major hassle, and to avoid this quandary, Windows XP keeps a copy of an old driver when a new version is installed. If the new driver has problems, the user can return to the previous version. However, this feature does not work with printer drivers. [4]


Fast User Switching allows another user to log in and use the system without having to log out the previous user and quit his or her applications. Previously on consumer versions of Windows, only one user at a time could be logged in, which was a serious drawback to multi-user activity. However, Fast User Switching requires more system resources than having only a single user logged in at a time and although more than one user can be logged in, only one user can be actively using their account at a time. This feature is not available when the Welcome Screen is turned off, such as when joined to a Windows Server Domain. [5] [6]

Remote Assistance permits support staff to temporarily take over a remote Windows XP computer over a network to resolve issues. [7] [8] As it can be a hassle for system administrators to personally visit the affected computer, Remote Assistance allows them to diagnose and possibly even repair problems with a computer without ever personally visiting it.

Remote Desktop is available only in Windows XP Professional. It is built on Terminal Services technology (RDP), and is similar to Remote Assistance, but allows remote users to access local resources such as printers. [9]. Any Terminal Services client, a special "Remote Desktop Connection" client, or a web-based client using an ActiveX control may be used to connect to the Remote Desktop. [10] (Remote Desktop clients for earlier versions of Windows have been made available by Microsoft. [11] This permits earlier versions of Windows to connect to a Windows XP system running Remote Desktop, but not vice-versa.) There are several resources that users can redirect from the remote server machine to the local client, depending upon the capabilities of the client software used:

  • File System Redirection allows users to use their local files on a remote desktop within the terminal session.
  • Printer Redirection allows users to use their local printer within the terminal session as they would with a locally or network shared printer.
  • Port Redirection allows applications running within the terminal session to access local serial and parallel ports directly.
  • Audio allows users to run an audio program on the remote desktop and have the sound redirected to their local computer.
  • Clipboard can be shared between the remote computer and the local computer.

Windows XP includes technology from Roxio which allows users to directly burn files to a CD through Windows Explorer. Previously, end users had to install CD burning software, such as Nero Burning ROM. Now, burning has been directly integrated into Windows' interface; users burn files to a CD in the same way they write files to a floppy disk or to the hard drive. Windows XP's CD burning support cannot handle ISOs or audio CDs, although the latter feature is integrated into Windows Media Player 8.

Windows XP includes ClearType sub-pixel font antialiasing, which makes onscreen fonts smoother and more readable on Liquid Crystal Display (LCD) screens, especially when italicized, although this causes a performance hit. ClearType does not necessarily have the same effects on older Cathode Ray Tube (CRT) monitors. However, as portable computers with LCD displays and new LCD monitors have become more common, there is a clear demand for ClearType.

Power management

In previous consumer versions of Windows, power management was based on the Advanced Power Management architecture. It was of limited use to most users and the feature was easily broken by the addition of hardware devices or software. Windows XP's power management architecture is based on the ACPI standard. It supports multiple levels of sleep states, including critical sleep states when a mobile (or UPS connected) computer is running out of battery power, processor power control (the ability to adjust the speed of the computer's processor on-the-fly to save energy), and the ability of Windows XP to turn off the power to the screen of a laptop when the lid is closed. In addition, it also dims the screen when the laptop has low battery power. [12]

Hibernate mode

This involves Windows dumping the entire contents of the RAM to disk and then powering down. On startup it quickly reloads the data. It allows the system to be completely powered off while in hibernate mode. This requires a file the size of the installed RAM to be placed in the system's root directory, using up space even when not in hibernate mode. Hibernate mode is disabled by default and can be disabled in order to recover this disk space.

The Windows hibernation feature conforms to the S4 Sleep State in the ACPI standard.

Standby (Sleep) mode

This involves Windows deactivating all nonessential hardware including the monitor, most fans, hard disks drives, and removable drives. This means that the system reactivates itself very quickly when 'woken up'. It does not allow the system to be powered down. In order to save power without user intervention a system can be configured to go to standby when idle and then hibernate if not re-activated.

The Windows Standby feature confirms to the S1 and S3 Sleep States in the ACPI standard.

Kernel improvements

Previous consumer versions of Windows were notorious for their instability and inefficiency at handling Random Access Memory (RAM). Most of them would not even be able to boot on a system with more than one gigabyte of RAM. Windows XP includes the Windows 2000/NT kernel, which was expressly designed for professional uses, and as such, has kept stability and efficiency in mind. [13]

The RAM and stability issues with older versions of Windows stemmed from the fact that they were actually 32-bit patches to what was essentially a 16-bit system. When Windows 95 was released, 32-bit processors had just arrived on the scene, and consumers were anxious to maintain compatibility with their applications that had been designed with a 16-bit processor and operating system in mind. As servers required maximum efficiency and stability, however, software vendors quickly upgraded their server software so as to be able to keep up with the pace of technology. As such, Windows' server product line's kernel was built with 32-bit processors in mind.

As Windows XP merged the consumer and server versions of Windows into one, it folded the user-friendly interface of Windows Me into the backend of Windows 2000. A drawback of this is that older software and drivers designed for 16-bit operating systems may no longer function on Windows.

Another common issue in previous consumer versions of Windows was that users frequently suffered from DLL hell, whereby more than one version of the same Dynamically Linked Library (DLL) was installed on the computer. As software relies on DLLs, using the wrong version could result in non-functional applications, or worse. Windows XP solved this problem by developing a "Side by Side" technology which keeps multiple versions of a DLL in the WinSxS folder and runs them on demand to the appropriate application.

Windows XP includes Simultaneous Multithreading Support, or the ability to utilize the HyperThreading feature of newer Intel Pentium 4 processors. Simultaneous Multithreading is a processor's ability to process more than one data thread at a time. Intel has described the effect as being that of having the processing power of two processors for only one.

The ability to boot in 30 seconds was a design goal for Windows XP, and Microsoft's developers made efforts to streamline the system as much as possible; many people have found that without extra services Windows XP can boot from the PC's power on self-test (POST) to the Windows GUI in about 30 seconds. End users can check how long their Windows machine takes to boot by using the now unsupported BootVis program.

User interface

Windows XP features a new task-based graphical user interface. The Start menu and search capability were redesigned and many visual effects were added, including:

  • A transparent blue selection rectangle in Explorer
  • A watermark-like graphic on folder icons, indicating the type of information stored in the folder.
  • Drop shadows for icon labels on the desktop
  • Task-based sidebars in Explorer windows
  • The ability to group the taskbar buttons of the windows of one application into one button
  • The ability to lock the taskbar and other toolbars to prevent accidental changes
  • The highlighting of recently-added programs on the Start menu

Windows XP analyzes the performance impact of visual effects and uses this to decide whether to enable them, so as to prevent the new functionality from consuming substantial additional processing overhead. These settings can be further customized by users. [14] Some effects, such as alpha-blending (transparency and fading), are handled entirely by many newer video cards. However, if the video card is not capable of hardware alpha-blending, performance can be substantially hurt and Microsoft recommends the feature should be turned off manually [15].

Default theme vs Classic theme

Windows XP adds the ability for Windows to use "Visual Styles" to change the user interface. However, visual styles must be cryptographically signed by Microsoft to run. Luna is the name of the new visual style that ships with Windows XP, and is enabled by default for machines with more than 64 MB of RAM. Luna refers only to one particular visual style, not to all of the new user interface features of Windows XP as a whole.

The Windows 2000 "classic" interface can be used instead if preferred.

Special versions

Microsoft has customized Windows XP to suit different markets and there are now several different versions available.

Windows XP for specialized hardware

In November 2002, Microsoft released four new versions of XP for specific hardware:

  • Windows XP Media Center Edition for special Media Center PCs. Windows XP Media Center Edition must be bundled with one of these computers; it cannot be purchased separately. This received an update in 2003, "Windows XP Media Center Edition 2003", which added additional features such as FM radio tuning. Another update was release in 2004, along with the release of MCE 2005, which was the first edition available for System Builders.
  • Windows XP Tablet PC Edition for specially designed notebook/laptop computers with a pen-sensitive screen supporting handwritten notes and portrait-oriented screens. It cannot be purchased separately from a Tablet PC.
  • Windows XP Embedded for specific consumer electronics, set-top boxes, kiosks/ATMs, medical devices, point-of-sale terminals, and Voice Over Internet Protocol (VoIP) components. This version is based upon the same binaries as Windows XP Professional.
  • Windows XP Professional 64-bit Edition (released on March 28, 2003) for manufacturers to install on computers with Intel Itanium processors. A version of Windows XP Professional 64-bit Edition designed for systems supporting the AMD64 instruction set, such as the AMD Athlon 64, AMD Opteron, and Intel EM64T-compatible processors, was released to manufacturing on March 30, 2005.

Windows XP Starter Edition

Windows XP Starter Edition (also called "XP Lite", not to be confused with Shane Brooks's XPLite) is a lower-cost version of Windows XP available in Asia and South America, including Russia and Brazil. It is similar to Windows XP Home, but has some features removed and some limitations added: display resolution can only be up to 800600 pixels, only three applications may be run at the same time, any application may have no more than three windows open, PC-to-PC home networking and printer sharing is not available and only a single user account is allowed. Added to the operating system are localized help features, country-specific wallpapers and screensavers and certain pre-configured settings to make it easier for novices to use.

According to a Microsoft press release, Windows XP Starter Edition is "a low-cost introduction to the Microsoft Windows XP operating system designed for first-time desktop PC users in developing countries". It is seen as an effort to fight unauthorized copying of Windows XP, and also to counter the spread of the open source Linux operating system which has been gaining popularity in Asia and South America.

Windows XP Home Edition N

In March 2004, the European Commission fined Microsoft €497 million and ordered the company to provide a version of Windows without Windows Media Player, claiming Microsoft "broke European Union competition law by leveraging its near monopoly in the market for PC operating systems onto the markets for work group server operating systems and for media players". Microsoft is currently appealing the ruling. In the meantime, the company plans to offer a court-compliant version of its flagship operating system under the name Windows XP Home Edition N, and at the same price as the full version. [16] [17]

Service packs

Microsoft infrequently releases service packs for its Windows operating systems to fix problems and add features.

Service Pack 1

Service Pack 1 (SP1) for Windows XP was released on September 9, 2002. Its most notable new features were USB 2.0 support and a Set Program Access and Defaults applet which allowed the user to control the default application for activities such as web browsing and instant messaging, as well as allowing the user to hide some of Microsoft's bundled programs.

LBA-48 was also added to SP1, which allowed the OS to view and use HDD space above 137 GB.

A Service Pack 1a was later released to remove Microsoft's Java virtual machine due to a loss in a lawsuit with Sun Microsystems.

Service Pack 1 also allowed Serial-ATA Drives to be detected during an Install from CD, but also blocked the two most used pirated Volume License CD-Keys used in Windows XP Professional to bypass Product Activation.

Service Pack 2

Service Pack 2 (SP2) was released on August 6, 2004 after several delays, and it focuses on security. Unlike previous service packs, SP2 adds new functionality to Windows XP, including an enhanced firewall, improved Wi-Fi support and a wizard utility, a pop-up ad blocker for Internet Explorer, and Bluetooth support. It also includes a new API to allow third party virus scanners and firewalls to interface with a new security center application, which provides a general overview of security on the system. This helps to suppress spyware and viruses. Other features include enhancements to the Internet Connection Firewall (ICF), now the Windows Firewall (which is also turned on by default), advanced memory protection that takes advantage of the NX instruction that is incorporated into newer processors to stop buffer overflow attacks, removal of raw socket support (which has caused a drop in "zombie" machines: infected computers that can be used remotely to launch denial of service attacks) [18], and improvements to e-mail and web browsing [19] (a full list of service fixes and modifications for SP2 is available on Microsoft's website). However, when the service pack was released some programs did stop working, and Microsoft officially listed several of them on its website [20]. The company AssetMetrix reports that one out of ten computers that upgraded to SP2 had severe compatibility problems with their applications. [21] [22]

SP2 also includes major updates to Windows XP Tablet PC Edition and Windows XP Media Center Edition.

SP2 also supports 24 new locales, including languages of Europe, South America, South Africa, Oceania and South Asia. [23]

Service Pack 2 is not without its critics. Thomas Greene from The Register claimed that SP2 was merely a placebo of sorts in terms of features, fixes, and security updates:

"While we found that there are indeed a few minor improvements worthy of acknowledgment, in particular, some rather low-level improvements that don't show to the admin or user, overall, SP2 did little to improve our system's practical security, leaving too many services and networking components enabled, bungling permissions, leaving IE and OE vulnerable to malicious scripts, and installing a packet filter that lacks a capacity for egress filtering." [24]

Although SP2 is delivered and installed to users who have automatic updates enabled, methods exist for uninstalling it. [25]

Service Pack 3 (pending)

In February of 2005, Mike Nash , an executive at Microsoft was quoted as saying there will be a Service Pack 3 for Windows XP. Little is known about it except that it may include the new version of Internet Explorer and will probably include security updates. [26]

Common criticisms of Windows XP

See also: Common criticisms of Microsoft

Security issues

Security concerns have long been an issue with Microsoft products. Windows XP has been criticized for its susceptibility to buffer overflows, malware, viruses, and worms.

Many attacks against Windows XP systems come in the form of e-mail trojan horses which are sent by worms. A user who opens one of the file attachments sent to him will unknowingly infect his own computer, which then e-mails the worm to more people. Notable worms of this sort which have infected Windows XP systems include Mydoom and Bagle.

In August 2003 the Blaster worm, which became one of the most well known Windows worms, exploited a vulnerability which is present in every unpatched installation of Windows XP and can compromise a system even without user action. Even security-conscious users can have trouble with Blaster, since it can infect a computer with a newly installed copy of Windows XP before the user has time to download security fixes [27]. Windows XP was also vulnerable to the Sasser worm, spread by using a buffer overflow in a remote service present on every installation. In May 2004, Sasser quickly spread through computers running Windows XP and Windows 2000.

No such worms have been seen since, as Service Pack 2 closed the loopholes these worms needed to spread [28].

Spyware and adware are a continuing problem on Windows XP and other versions of Windows. These usually unwanted programs can cause system instability, display pop-up ads, and track a user's activities for marketing purposes. Often these programs are included with seemingly harmless downloads. Spyware is also a concern for Microsoft with regards to service pack updates. Barry Goff, a group product manager at Microsoft, said some spyware could cause computers to freeze up upon installation of Service Pack 2 [29].

In January 2005 Microsoft launched the beta version of their Anti-Spyware system, a free download, which removes spyware from user's computers [30].

This security issue is compounded by the fact that users, by default, get an administrator account that gives them full access to the system. This means that any damage that is done to a compromised machine is not limited if the administrator's account is cracked into. Nicholas Petreley for The Register notes that "Windows XP was the first version of Windows to reflect a serious effort to isolate users from the system, so that users each have their own private files and limited system privileges." [31], however Rob Pegoraro, for the Washington Post noted that "XP Home's "limited account," the only other option, doesn't even let you adjust a PC's clock." [32]

Windows XP offers some useful security benefits, such as Windows Update, which can be set to install security patches automatically, and a built-in firewall. SP2 sets the firewall to be turned on by default, and also adds increased memory protection to let the operating system take advantage of new NX technology built into 64-bit CPUs such as the AMD 64. This allows Windows XP to prevent code from being executed on areas of memory flagged with an NX bit, and thereby to stop buffer overflow exploits from running arbitrary code.

Windows, with its large market share, has traditionally been a tempting target for virus creators. Also, security holes often aren't visible until they are exploited, making preemptive action difficult. Microsoft executives have stated that the release of patches to fix security holes is often what causes the spread of exploits against those very same holes, as crackers figured out what problems the patches fixed then launch attacks against unpatched systems.

Perhaps the greatest threats against Windows security are the actions of Windows users themselves. There is little defense against a user opening an e-mail attachment without realizing that it is malicious (the default setting of Windows XP to hide file extensions doesn't help in this regard), or failing to keep reasonably current on Windows Update patches.

Product activation

Windows XP has been criticized for its product activation system. The system was introduced by Microsoft to curb illegal distribution of Windows XP [33], but while product activation and licensing servers are common for business and industrial software (especially software sold on a per-user basis for large sums of money), Windows XP gave many casual computer users their first introduction to "phone home" protection that requires the computer or the user to activate with Microsoft within a certain amount of time in order to be allowed to continue using the operating system. If the user's computer system ever changes — for example, if two or more relevant components (see list below) of the computer itself are upgraded — Windows may refuse to run until the user reactivates with Microsoft.

Privacy fears were raised about the nature of the data transmitted to Microsoft. Microsoft then released details about the nature of the information transmitted [34]. It includes a cryptographic hash of the following ten values:

  • Display adapter name
  • SCSI adapter name
  • IDE adapter name
  • Network adapter MAC address
  • RAM amount (as a range, e.g. 0–64 MB, 64–128 MB, etc.)
  • Processor type
  • Processor serial number (if applicable)
  • Hard drive device
  • Hard drive volume serial number
  • CD-ROM/ CD-RW/ DVD-ROM identification

This information is used to seed the generation of a number which, along with the CD Key and country of installation, is transmitted to Microsoft. According to Microsoft, no specific details about the hardware are transmitted.

Entering a specially crafted Volume License Key (VLK) into a copy of Windows XP Professional disables Windows Product Activation entirely. Copies of Windows XP Professional with WPA disabled through the use of a VLK are commonly referred to as "Windows XP Corporate Edition". A VLK can be entered during installation of Windows or afterwards, by invoking the Windows Product Activation Wizard. According to Microsoft, 90% of pirated installations of Windows XP use VLKs to circumvent WPA. The most famous VLK is one beginning with FCKGW, which was released along with the first pirated copies of the final version of Windows XP.

User interface and performance

Critics have claimed that the default Windows XP user interface (Luna) adds visual clutter and wastes screen space while offering no new functionality and running more slowly. Supporters of the new interface praise its task-oriented nature and the automatic grouping of related windows on the taskbar to reduce clutter, and point out that the higher system requirements of Windows XP allow it to easily handle the increased processor demand; with a small amount of tweaking, it is possible to return to the Windows 2000 look, which is faster, but many consider this less visually attractive.

CNET's web site lists hundreds of positive and negative reviews of Windows XP Home [35] and Professional [36] from users. David Coursey, Executive Editor of ZDNet's AnchorDesk [37], and Paul Thurrott, who runs SuperSite for Windows [38] have both written positive reviews of the operating system.

Integration of operating system features

In light of the Microsoft antitrust case which resulted in Microsoft being convicted for illegally abusing its operating system monopoly to overwhelm competition in other markets, Windows XP has drawn fire for integrating user applications such as Windows Media Player and MSN Messenger into the operating system, as well as for its close ties to the Microsoft Passport network service.

In 2001, ProComp claimed that the bundling and distribution of Windows Media Player in Windows XP was a continuance of Microsoft's anticompetitive behavior [39], and that the integration of Passport into Windows XP was a further example of Microsoft attempting to gain a monopoly in web services [40]. Both of these claims were rebutted by the Association for Competitive Technology (ACT) and the Computing Technology Industry Association (CompTIA) [41] [42]. ProComp is a group including several of Microsoft's rivals, including Oracle, Sun, and Netscape. ACT and CompTIA both have portions of their funding donated by Microsoft. The battle being fought by fronts for each side was the subject of a heated exchange between Oracle's Larry Ellison and Microsoft's Bill Gates[43].

Microsoft responded on its "Freedom to Innovate" web site, pointing out that in earlier versions of Windows, Microsoft had integrated tools such as disk defragmenters, graphical file managers, and TCP/IP stacks, and there had been no protest that Microsoft was being anticompetitive. Microsoft asserted that these tools had moved from special to general usage and therefore belonged in its operating system.

To avoid the possibility of an injunction which might have delayed the release of Windows XP, Microsoft changed its licensing terms to allow PC manufacturers to hide access to Internet Explorer (but not remove it). Competitors dismissed this as a trivial gesture [44]. Later, Microsoft released a utility as part of the SP1 which allows icons and other links to bundled software such as Internet Explorer, Windows Media Player, and MSN Messenger to be removed. The components themselves remain in the system; Microsoft maintains that they are necessary for key Windows functionality (such as the HTML Help system and Windows desktop), and that removing them completely may result in unwanted consequences. One critic, Shane Brooks, has argued that Internet Explorer could be removed without adverse effects, as demonstrated with his product XPlite [45]. Dino Nuhagic created his nLite software to remove many components from XP prior to installation of the product [46].

In addition, the first release of Windows XP, the "Buy Music Online" feature always used Microsoft's Internet Explorer rather than any other web browser that the user may have set as his/her default. Whether this flaw was intentional or simply an oversight is unclear. Under pressure from the United States Department of Justice, Microsoft released a patch in early 2004, which corrected the problem [47].

Copying restrictions

Microsoft Windows XP service packs are designed so that they will not install on computers running installations of Windows XP that use certain well known pirated product keys. These product keys are unique to each boxed (or bundled) copy of Windows XP and are included with the product documentation, but a small number of product keys have been posted on the Internet and are responsible for a large number of unauthorized installations. The service packs contain a list of these keys and will not update copies of Windows XP which use them.

Microsoft developed a new key verification engine for Windows XP Service Pack 2 that could detect illicit keys, even those that had never been used before. After an outcry from security consultants who feared that denying security updates to illegal installations of Windows XP would have wide-ranging consequences even for legal owners, Microsoft elected to disable the new key verification engine. Service Pack 2 only checks for the same small list of commonly used keys as Service Pack 1. This means that while Service Pack 2 will not install on copies of Windows XP which use the older set of copied keys, those who use keys which have been posted more recently may be able to update their systems.

See also


External links

Windows XP Editions and Special Versions
Service Pack 2
Useful sites

Last updated: 05-13-2005 07:56:04