Vista:

1. Go to Start and type in "sysdm.cpl" (without the quotes) and press Enter
2. Click on the Advanced tab
3. Click on the Performance Settings button
4. Click on the Advanced tab
5. Click on the Virtual Memory Change button
6. Uncheck the "Automatically manage paging file size for all drives" box (it's the default)
7. If the above box isn't checked, then make a note of what the paging file settings are
8. Click on the "No paging file" radio button, then click on "Set"
9. Answer Yes to the confirmation dialog that pops up.
10. Click on OK 3 times (to close all the Windows)
11. Reboot the system (this will delete the paging file)
12. Once Windows starts, go to Start and type in "sysdm.cpl" (without the quotes) and press Enter
13. Click on the Advanced tab
14. Click on the Performance Settings button
15. Click on the Advanced tab
16. Click on the Virtual Memory Change button
17. Place a checkmark in the "Automatically manage paging file size for all drives" box (it's the default)
18. If the above box wasn't checked at first, then re-enter the paging file settings that you noted in Step 7
19. Click on "Set" (it'll be greyed out if you checked the box 2 steps earlier
20. Click on OK 3 times (to close all the Windows)
21. Reboot the system (this will recreate the paging file)