Check for a User~tmp.@01 folder in the root of the drive in which Windows is installed. If a missing user account folder exists in the User~tmp.@01 folder but cannot be accessed in Windows XP (because the folder name ends with a period. Rename the folder from the command prompt by using the 8.3 filename so that it can be viewed using the Windows File Explorer. Instructions follow...
1) Click Start , and then click Run.
2) Type cmd , and then click OK
3) Type cd\ , and then press ENTER
4) Type cd\user~temp.@01 , and then press ENTER
5) Type dir /x , and then press ENTER. Take note of the short file name for the user account folder. For example, the short file name for "User Name" might be "USERNA~1"
6) Type ren "userna~1 username", and then press ENTER
7) Type exit, and then press ENTER
8) Click Start, and then click Run
9) Type %homedrive%\user~tmp.@01\username, and then click OK
10) This folder and subfolders should contain the files from the missing user account.