The user has probably deleted rundll32.exe, rundll.exe, rnaapp.exe and/or other programs key to W95 operation.
The fastest method is a reinstall, assuming there is no system backup, which unfortunatly is about 95% of the time.
You can try to copy these missing files from another computer with the same version but it is actually very tedious work.
If you are familiar with windows you can take a look and see if the program left behind an uninstall.log which can give you the details of which files were deleted.
A long shot...check and see if they are in the Windows Trash folder. If they are then copy them back to the Windows and Windows\System directories.
Good Luck,
Al Franco, II