Offline Files

I am running Vista Home Ultimate and cannot get offline files active.
Rightclicking on a shared folder (on XP pro system in my workgroup -- no
domain and no server).
selection for offline files is not present.

I then use control panel to "enable" offline files --- they are arleady
enabled!
but the fine print below the disable button is a message that says
"Offline Files is enabled but not yet active. Restart this computer to
activate Offline Files."

Restarting has no effect (also disable then restart then enable then restart
does not work). I have looked at other posts with similar problems some
listed under synch problems but most of them at least got to their offline
files at least at some time.

What does it take for Offline Files to "Activate"??