I have Vista Home Premium 64 running on a laptop, XP Pro on another laptop, Vista Ultimate 64 on a desktop. I've done the regedit "LocalAccountTokenFilterPolicy" so I can connect to C$. I have no trouble accessing my laptop from my XP machine but cannot access from the Vista Ultimate Desktop. I can however, access C$ from my Vista Home Premium on the Vista Ultimate. As far as I can tell, the settings are the same on each machine. I've allowed browsed my network via \\computername\c$\directorynamehere and don't want to change but this is really getting me. Any ideas on might be causing the problem or where I can look?