I have had this same problem for the last week. Can not connect to server. It is possible that it is down for maintenance. I hope that it is up and running soon. I have completed tasked done myself.

Captain-Shown

Uploads are still possible although it usually takes many attempt since the network is being pounded by thousands of computers that are trying to get work.
The main server that supplies the work died. A replacement is being rushed in by Sun Microsystems on Monday. We may start getting work again by Wednesday if all goes well with the installation and no corruption of the hard drives occurred. It will take several days to feed all those hungry computers looking for something to crunch. I wouldn't expect things to be back to normal until the end of the week.