Win 8.1 Group Policy Management

[LukeC]

I'm attempting to alter a policy using windows 8.1 machines, I can view the settings in the right hand pane but when I come to edit it I get the following error below

 

It only seems to happen on this policy, I can edit the policy on win 7 machines and 2008 machines.

any suggestions? thanks

[cromertech]

Does this group policy object have any deprecated settings. I'm thinking of legacy internet settings or something like that. Can you run GP modelling on a machine/user combination that uses the policy?