Windows XP 5.1.2600.5687

Windows XP is a desktop operating system from Microsoft for PCs, released in Home Edition and Professional editions, with separate 64-bit editions for specific processors. It is built on the Windows NT and Windows 2000 code base and brought that protected-memory design to home computers as well as business desktops. Microsoft no longer supports Windows XP.

The Start menu, taskbar and folder tasks

The Windows XP Start menu adapts to the person using it. It lists the programs launched most often, keeps the default web browser and e-mail program pinned at the top, and gives one-click access to Help and Support and system settings. Users can customize it or switch the whole desktop back to the classic Windows 2000 look.

The taskbar groups windows from the same application. Nine open Word documents, for example, collapse into one button with a count. Clicking it opens a vertical list of the files. Users can cascade, tile or minimize the group together.

Folder windows show a task pane next to the files. Selecting a file brings up actions suited to that file type, such as rename, move, copy, e-mail, delete or publish to the web. These commands are therefore not limited to right-click menus.

Several people on one PC

Fast User Switching lets a second person log on without closing the first person’s programs. Each account runs in its own Terminal Services session. A financial program left open by one user therefore keeps running while another user works, and their data stays separate. In Home Edition the feature is on by default. In Windows XP Professional it works only on stand-alone or workgroup computers, not on a PC joined to a domain.

Undoing system and driver changes

System Restore watches system files and some application files and stores copies before they change. Windows creates restore points daily and before events such as installing a program or driver. Users can add named points at any time. Rolling back returns Windows XP to an earlier state without touching documents, pictures or e-mail. This also means it cannot recover deleted personal files.

Driver Rollback covers a narrower problem. When a driver is updated, Windows keeps the previous package. The Roll Back Driver button on the device’s Driver tab in Device Manager reinstalls it. Only one earlier driver is kept, and printers are excluded.

When Windows will not start, the Recovery Console offers a command line for stopping services, formatting drives and copying files to repair the installation. Windows File Protection restores core system files that an installer overwrites.

Remote Desktop and Remote Assistance

Remote Desktop is a Professional feature. It lets a user work on a Windows XP Professional PC from another Windows computer over a LAN, VPN or dial-up link. Programs run on the remote machine; only keyboard and mouse input and screen output cross the network. Local drives, printers, serial ports, audio and the clipboard can be redirected into the session.

Remote Assistance, in both editions, is for getting help. The user sends an encrypted invitation through Messenger, e-mail or a saved file. By default, a session password protects the invitation and is passed on separately. The helper can then watch the screen or, with the user’s permission, take temporary control. Invitations expire after a set time, from one minute to 99 days.

Home networking and the firewall

The Network Setup Wizard builds a small network without networking knowledge. It detects which adapter reaches the Internet, gives each PC a friendly name, and sets up file and printer sharing. Internet Connection Sharing lets several computers use one dial-up or broadband connection, with the sharing PC handing out addresses and translating traffic. Network Bridge joins different media, such as Ethernet and wireless, into one network without extra hardware. A WebDAV client opens files on web servers as if they were network shares.

The Internet Connection Firewall drops unsolicited incoming connections. The firewall blocks traffic that did not start inside the protected computer or network. This also stops outside access to shared folders and printers.

Encryption, passwords and restricted software

The Encrypting File System in Windows XP Professional encrypts files when the encryption attribute is set on a file or folder in Windows Explorer. Setting this attribute works just like setting read-only or hidden. Windows creates keys automatically for each user. Decryption is transparent to the owner, and several users can be given access to the same encrypted file.

Credential Manager stores passwords and certificates for network resources and applications. Users enter them once, and Credential Manager supplies them automatically later. Software Restriction Policies let administrators decide which programs may run or block specific code, such as scripts in e-mail attachments.

Running older programs

Compatibility mode lets a user mark an individual program to run as if on Windows 95, 98, Me or NT 4.0. Side-by-side assemblies, stored in the WinSxS folder, keep several versions of a system component installed at once. A program therefore keeps the DLL version it was built for even after another program installs a newer one.

Music, video, discs and photos

Windows Media Player plays CDs and DVDs, rips and burns audio CDs, tunes Internet radio and copies music to portable devices. Windows Movie Maker captures video from suitable hardware, edits video and audio clips, and saves the result as Windows Media files. Users can burn CD-R and CD-RW discs by dragging files in Windows Explorer. Windows prepares the full disc image on the hard drive before writing to avoid interrupted burns. Picture folders offer slideshows and can e-mail photos.

Laptops, displays and offline work

On notebooks, Windows XP lowers processor speed on battery and dims the screen. It can hibernate automatically when the battery runs low, writing memory to disk so programs reopen where they were. ClearType renders text at three times the horizontal resolution to sharpen it on LCD screens. DualView drives a laptop panel and an external monitor independently from one display adapter. In Professional, Offline Files keeps chosen network folders available while disconnected, synchronizes changes on reconnection and can encrypt the local cache.

Home Edition versus Professional

Both editions share the interface, System Restore, Remote Assistance, the firewall and the media tools. Windows XP Professional adds the business and power-user features: