Today I got an email from a colleague saying that our corporate site was down; after checking, I noticed that my own personal blog was down as well. I got a blank page! No more WordPress backoffice! Static pages and images worked well, however. And the logs weren't very helpful either.
Intrigued, I thought it was a cache problem (both sites use W3 Total Cache, which sometimes misbehaves). But no: I was getting far stranger error messages. After cleaning up everything on .htaccess I got a message saying that PHP was missing the mysql extension!
Oh my. I confirmed that via phpinfo(). Wow! MySQL support on PHP 5.3 was gone!
I'd expect a gazillion messages complaining about that here in the forums, but I didn't find any, so I guess this didn't happen to everyone. In fact, I've checked on other sites I have here, and, so far, I just found those two missing MySQL support on PHP 5.3...
Well, the fix is easy: just go to the DH Control Panel, select the domains which lost MySQL access, and save it. DH will work its magic "reinstalling" PHP 5.3 again and everything will work as before. Whew!
I'm just leaving this article here in case you've encountered the same error and just panicked.