Adding permissions "NT Service\mpssvc" not working - the account is not found. Firewall not running (error 5 (0x5))

Hi all,

i have a problem with the firewall-service on a Windows 2008 Std SP2. The firewall service does not start. Access denied problem. I can see that on some registry-keys the permissions for the "NT Service\MpsSvc" account are missing.

I found some similar threads, and here is decripted what to do.

But if i try to add the permissions for "NT Service\MpsSvc" the server does not find this account - so, i cannot add it to the registry key.

What i have to do that i can select this account ?

Thanks

Bruno