How to manually remove Windows XP and then restore Windows 95, Windows 98, or Windows Millennium Edition

This article describes the options that are available when you remove a Microsoft Windows XP upgrade and restore Microsoft Windows 95, Windows 98, or Windows Millennium Edition.

Note To perform the procedures that are described in this article, you must reinstall Windows 95, Windows 98, or Windows Millennium Edition, and all your other programs. This article does not describe how to recover a Windows 95, Windows 98, or Windows Millennium Edition installation.

For additional information about how to recover the previous installation of Windows 98 or of Windows Millennium Edition, click the following article number to view the article in the Microsoft Knowledge Base: The "More Information" section discusses the following issues:

• Is the file system formatted as FAT, FAT32 or as NTFS file system? If the file system is in NTFS, see the "Removing NTFS" section.
• Do you want to save files? If yes, see the "Renaming folders" section.
• Is Windows installed in the Windows folder? If yes, see the "Renaming folders" section.
• Do you have to free up space so that you can install Windows 95 or Windows 98? If yes, see the "Freeing up disk space" section.

If you backed up all your data before you installed Windows XP, or you do not have any data that you must keep, you can reformat the hard disks in the computer and reinstall Windows 95, Windows 98 or Windows Millennium Edition. For more information, see the "Removing NTFS" section.

Warning: When you format a disk, you delete all the files and all the data. Format a disk only if you have backed up all the files that you want to keep.

Setting up

1. Identify the file system that you are using:
   1. Click Start, and then click My Computer.
   2. Right-click the disk that you want, and then click Properties.
   3. Look for the File System entry.
      • If the disk is formatted in NTFS, your options for returning to Windows 95, Windows 98, or Windows Millennium Edition are limited. Those operating systems do not read or recognize NTFS, and you cannot convert the disk to use the FAT or FAT32 file systems. The startup disk that you use and the drive where you want to install Windows 95, Windows 98, or Windows Millennium Edition cannot use NTFS. Microsoft does not support any third-party solutions for the conversion of NTFS to FAT or to FAT32.
      • If the drive uses the FAT file system, you can install any operating system. If the drive uses the FAT32 file system, you can install Windows 95 OEM Service Release 2 (OSR2) or later.
2. Determine how much disk space is available on your computer, and see the documentation for the earlier operating system to determine how much disk space you must have.
3. Locate your Windows 95, Windows 98, or Windows Millennium Edition startup disk.
   
   Note You can create the Windows 95 Startup disk, the Windows 98 Startup disk, or the Windows Millennium Edition Startup disk on any Windows 95-based, Windows 98-based, or Windows Millennium Edition-based computer. The startup disk must correspond with the operating system that you are installing.
   
   For additional information, click the following article numbers to view the articles in the Microsoft Knowledge Base:
   267287  (http://support.microsoft.com/kb/267287/ ) How to create a startup disk in Windows Me
   296532  (http://support.microsoft.com/kb/296532/ ) How to create a Windows 98 startup disk
   284943  (http://support.microsoft.com/kb/284943/ ) How to create a Windows 95 startup disk in MS-DOS
4. Use the startup disk to start your computer. Verify that you can read the CD-ROM drive, and then type sys c: at a command prompt.
   
   Important: This command transfers the Startup files to drive C and copies the boot sector. After you run this command, you can no longer start Windows XP.

Renaming folders

If you install Windows 95, Windows 98, or Windows Millennium Edition on the same drive where Windows XP is installed, you must rename certain folders to prevent possible conflicts.

Note If you reformat the hard disk, you do not have to rename any folders.

To rename the Program Files folder and the Windows folder, type the following commands at a command prompt, and press ENTER after each command:

• ren c:\progra~1 c:\files.old
• ren c:\windows c:\windows.xp

Removing NTFS

To remove the NTFS file system, reformat the hard disk to use the FAT or FAT32 file system. To do so, use the Windows XP startup disks. If your computer supports a bootable CD-ROM, you can also use the Recovery Console tool on the Windows XP CD-ROM. If you reformat or repartition a disk, you delete all the data that is on the disk. Therefore, make sure that you back up your data before you reformat the disk.

To use Recovery Console to reformat a drive, follow these steps:

1. Use the Windows XP CD-ROM or the startup disks to start the computer.
2. When the Welcome to Setup screen appears, press F10.
3. In Recovery Console, specify the appropriate installation, and then use your Administrator credentials to log on.
4. Type map, and then press ENTER.
5. Note the drive that you want to reformat. The drive letters may be different in Recovery Console from what they are in Windows XP.
6. Type the following command at a command prompt, and then press ENTER:
   format x: /fs:fat32
   Where x is the letter of the drive that you want to format, and FAT32 is the file system that you want to use.
7. Type y, and then press ENTER. When the formatting is completed, type exit. and then press ENTER to restart the computer.

Freeing up disk space

If you have low disk space, you can safely delete the following files and empty the following folders:

• Empty all Windows XP recycle bins.
• In Microsoft Internet Explorer, delete all temporary Internet files, and clear the history files.
• Delete the Pagefile.sys and Hiberfil.sys files.
  
  Note You must delete the Pagefile.sys file in Safe Mode with Command Prompt.

Removing Windows XP files

The following files are hidden files. These hidden files are located in the root folder of the drive that is used to start the computer. Typically, this is drive C (the first drive letter that is available for hard disks).

To remove the Windows XP system files, follow these steps:

1. Start Windows Explorer.
2. Click View menu, and then click Folder Options.
3. Click the View tab, click Show all files, and then click OK.
4. In the root folder of drive C (or the boot drive), delete the following files:
   • Boot.ini
   • Ntbootdd.sys
   • Ntdetect.com
   • NTLDR
5. On the drive where Windows XP is installed, delete the following files if they exist:
   • Hiberfil.sys
   • Pagefile.sys
     
     Note You must delete the Pagefile.sys file in Safe Mode with Command Prompt.
6. Delete the following folders if they exist:
   • Windows
   • Program Files
   • Documents and Settings

Running the Setup program in Windows 95, Windows 98, or Windows Millennium Edition

To run the Windows Setup program, start your computer by using the Startup disk for the Windows operating system that you are installing. After you access the CD-ROM drive, type the following commands, and press ENTER after each line: Where x is the letter of your CD-ROM drive.

Note In Windows Millennium Edition, the first command may not work and may generate an error message. Typically, this problem does not prevent a successful installation. The Windows 95, Windows 98, or Windows Millennium Edition CD-ROM have a Setup.txt file that explains how to run the Setup program. There are more instructions for the Setup program in the Getting Started guide that is included with each of the operating systems.