I am trying to upgrade a member server to a second domain controller in my SBS domain. Both servers are located at different sites (1 in Glasow the primary & the other In London) Both LANs are connected by a VPN with policies that allow all traffic between each LAN.  When I try to promote the member server i get about 3/4 of the way through when I get the following error

The operation failed because: The Active Directory Installation Wizard was unable to convert the computer account (servername)$ to a domain controller account.  "Access is denied."

Then it askes me to type the name and password of a user who has sufficiant privilages to an addition DC.

Needles to say, the account is the administrator and I am using the correct password. There doesnt seem to be a connectivity issues between the 2 sites as users in London are using the Glasgow DC for there logons. Does anyone have any ideas about this?

Any help would be appriciated

Thanks for you help anyway.