Have Just upgraded my 1and1 virtual server. The upgrade was from business level to professional level - increased memory / disk space.
When trying a Dotnetnuke application I get the error "Service Unavailable". I get the same message when working with any of the PLESK screens - note Plesk has just been installed.
I have registered this with 1and1 but they say it will be 1 to2 days for them to look at it.
I'm looking for a very fast response (today) to get this fixed.
My un-educated guess is connectivity to database, but am not at all sure.
Ideally, you should be familiar with Dotnetnuke.