I've had some hacking into my servers and htaccess files across all my wp web sites recently. Least this is the conclusion I've come to?? I still haven't got my sites up after two weeks now.
Not only that i didn't know where to start because i could not even log into the servers and the ftp stopped as well.
So far i have found that each of the htaccess file have been either changed, deleted or removed, something different for each site.
I get 500 internal errors on loading any site 2.9.2. There is some villans out there that really try to mess your world around.