LZ,,, windows will use virtual memory, which is placed on drive C by default, which will probably take up more than one G space. You can set the virtual memory to a different drive letter.

Setting method: My Computer-> Properties-> Advanced-> Performance-> Settings-> Advanced-> Virtual Memory

Clear IE temporary files, recycle bin,

Delete the c:\windows\temp directory and the c: \ documents and settings \ user name \ local settings \ temp directory.

Windows often patches, and after patching, some files will be left for recovery, but they are generally not used and can be deleted.

Delete location: C:\ WINDOWS \ $ HF _ MIG $ C directory of all files: \ Windows \ $ NTUninstallKB * * $

After the upgrade, some files will remain on drive C. You can delete the files under c: \ program files \ Microsoft SQL Server \ 90 \ setup bootstrap, which is about 500M.

After cleaning up these, I can probably restore 1~3G space. This is all my experience, hands-on! !