I had this recently - could get everything but my e-mails. It was classed as 'Error 103', if I remember correctly. I logged the error several times but then it just came back.....after 4 weeks. I had just about given up and thought I'd just try it and bingo, back again. No explanation as to what happened or why it was out for so long (longest four weeks ever!) but all working fine again now.
Sorry - not much help! The site does say this kind of error is usually sorted within an hour, but if longer than 4 hours to log it as a problem. I guess four weeks was something of an anomaly!