I first discussed the Limited Virtual Memory error in tip 2402 - Windows NT / Windows 2000 issues 'Limited Virtual Memory' error on startup?

If you receive the following error after installing or removing a hard drive, or a device that looks like a hard drive to Windows 2000, you may need to use one of the procedures in this tip to recover:

Limited Virtual Memory
Your system is running without a correctly sized paging file. Please use the virtual memory option of the System applet in Control PaneL to create a paging file, or to increase the initial size of your paging file.

This problem is symptomatic of an incorrect drive letter in the HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices key.

To fix this disaster:

01. Start the Recovery Console.

02. Type the number that represents the damaged Windows 2000 installation.

03. Type your administrator password.

04. Type CD %SystemRoot%\System32\config.

05. Type ren system system.old.

06. Type cd %systemroot%\repair.

07. Type copy system %systemroot%\system32\config.

08. Type exit.

09. After your system starts, log on with administrative privileges.

10. Start / Run / regedt32 / OK.

11. Highlight HKEY_LOCAL_MACHINE.

12. On the Registry menu, press Load Hive.

13. In the Load Hive dialog, navigate to System.old in the %SystemRoot%\System32\Config folder and press Open.

14. Type recovery into Key Name and press OK.

15. You can compare the contents of HKEY_LOCAL_MACHINE\recovery\MountedDevices with the contents of HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices.

16. Select the HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices key and press Save Key on the Registry menu.

17. Select Desktop from the drop-down box and type mounteddevices in the File name box. Press Save.

18. Select the HKEY_LOCAL_MACHINE\recovery\MountedDevices key.

19. Use the Registry menu to Restore a saved key. In the Restore Key dialog, select the mounteddevices file that you saved in step 17.

20. Press Yes to confirm the operation.

21. Select the HKEY_LOCAL_MACHINE\recovery\MountedDevices key.

22. Press Unload Hive on the Registry menu, pressing Yes to confirm.

23. Close Regedt32.

24. Shutdown Windows 2000.

25. Start the Recovery Console.

26. Type the number that represents the damaged Windows 2000 installation.

27. Type your administrator password.

28. Type CD %SystemRoot%\System32\config.

29. Type ren system system.bak.

30. Type ren system.old system.

31. Type exit.

NOTE: If you have an alternate install on a different partition, you can simply replace the HKEY_LOCAL_MACHINE\SYSTEM\MountedDevices key with the one from the parallel install:

1. Boot the parallel installation.

2. Use Regedt32 to Highlight the HKEY_LOCAL_MACHINE hive.

3. On the Registry menu, Load Hive.

4. In the Load Hive dialog, navigate to System in the %SystemRoot%\System32\Config folder of the broken installation and press Open.

5. Perform steps 14 - 23.

6. Shutdown the alternate install and boot to the repaired installation.