Hmm, only thing I can imagine is that it really DID went corrupt. Only thing I think you can do is re-download. To save you a lot of hassle,
here is the link to our team page with ready-to-go links to download locations. I have no experience yet (not seen them before) with the errors you described, that's why I think they must be corrupt. Do you use download accelerators which chop files up into multiple parts for download, could also be a reason...
To be sure, what OS do you use and what files for seti did you get? Succes!
Murphy
(for ALL the info you need to setup and join a team, see our teampage:
http://overclockers.ws/seti/oc_seti.htm )