Confusing PDO-only problem : Can't connect through socket/Access denied/Can't connect to server (shared host)

Question

So the problem changed from what it was, i\'ll leave the original question below to prevent bad reviews on answers like I had after someone editing his question I answered :

Answer 1

I just solved a similar issue. My guess is you probably replaced your mysql_connect() statement with the PDO equivalent. Don't forget you still have lots of other code dependent on that old connection statement. Try keeping the mysql_connect in place while writing in the PDO code.