Can't Log into BOE

I am trying to maintain a Crystal Reports 2011 installation. I didn't write the reports nor set up the instance. All reports and BOE are on the same machine. I can no longer log into the Business Objects Repository even though the machine name, user, password and authentication method of Enterprise have been input. The only thing that has changed is that the Win 2008 server, which resides on AWS, has been upgraded, which changed the internal address of the machine. Is that the potential problem and where would this be fixed?

Thanks

Mike