I've been banging my head against a brick wall with 1 iMac out of 150 which refuses to take WGM preferences.

Server and iMac both on 10.6.8.
iMac bound to AD and OD (in that order)

Tried the following:

Re-imaging mac using Deploy Studio and same image used for all other clients.
Clearing DNS (on windows DC) and re-adding records
Clearing iMac from AD and OD and re-joining both.
Applying policy in WGM on the individual Mac rather than through a group
Clearing MCX cache
Changing Mac name as part of re-image.
Deleting contents of /Library/Managed Preferences

Any other suggestions would be welcome

Many thanks