Possible Duplicate: Is it safe to delete from C:\Windows\Installer? The folder "C:\Windows\Installer" on my Windows XP contains 2 GiB of .msi files. I know they are Windows Installer cache ...
I can't delete C:\Config.Msi\75ce84f.rbf. it's not readonly, system or hidden it's not in use by another process (according to Process Explorer) the NT security permissions aren't the problem either ...