I just tried to get to my blog and got an error that a plug-in needed to be enabled. I then tried to go to the blog main section and got the same error. 
Message
To use this product the plugin system must be enabled.
I'd like ^^^^ if I could.
Looking into it...
Sonic, not that is appears to matter for this one - but the first thing I did was log out and clear cookies & caches anyway. Obviously that didn't work. Just to let you know.
Note to self - when this gets resolved make back-up copies of current blog versions.
When I go to What's New - My Posts I get this error, Please add more constraints to your search. Searches that return all or most of the database are a bad idea.