Here's a +1 to Beyond Compare; I use it for every upgrade (comparing user changes).

But as Ruben says, the first step should be trying to access the admin center and then looking at your log files after you get a blank page (so the error is one of the newer actions).

I am a Web Development Contractor, I do not work for UBBCentral. I have provided free User to User Support since the beginning of these support forums.
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