Invalid user name or password when specifying user account for management server service

Hello,

I am trying to upgrade my backup server to the latest build. I have been successful installing each of the modules except the management server. When installing I am prompted to specify the credentials of a user account for acronis management server service (it offers as default the currently logged on user, myself). I use an existing domain account which has log on as a service rights and is a member of backup operators. This is the account I used when I did the original installation and the account that is currently being used. To test I use my own credentials (I am domain admin) and it accepts them. I can't figure out what's wrong.

Can someone point me in the right direction?

Thanks a million,

M