How To Delete All XP's Temporary Files With Disk Cleanup

Temporary files are usually created by applications that need to store information that is either too big for storage in RAM or that needs to be saved in non-volatile memory (such as a hard drive).
Microsoft Windows uses many temporary files to store data about the users' web browsing history and settings. The most common files associated with Windows temporary files are index.dat and the entire Cookies folder under Documents and Settings that stores HTTP cookies.

You can use the Disk Cleanup built in utility to delete the temporary files in Windows XP. Even so this will now clean all the files, because it is set not to delete files that have been accessed in the last seven days. However with a little trick made to the Windows Registry you can get rid of all your temporary files. Here is how:

Note: Because you will make changes to the registry, a good idea is to backup it first.

1. Open the Registry Editor by clicking Start -> Run... and typing regedit. Click OK.
2. Navigate to HKEY_LOCAL_MACHINE -> SOFTWARE -> Microsoft -> Windows -> CurrentVersion -> Explorer -> VolumeCaches -> Temporary Files.
3. In the right pane look for a value named LastAccess and double-click to modify it.
4. In the Value data field put 0 instead of 7. Click OK.
5. Restart your computer and from now on all your temporary files will be deleted no matter when they have been accessed.