VAC issue

we have an issue when we try to amend a desktop policy setting (amend outlook add-in behaviour from HTTP to Normal). We can make the change however when we click OK or APPLY the VAC just hangs. It happens on all our EV servers (we have 9) in this particular EV environment which makes me think that it cannot be an issue with the server itself

i dotn suppose anyone has encountered anythign like this before have they?

thanks