I am new to macs. I clicked "software update" and it downloaded 9 things. everything from iworks 09 to itunes and mac os X update. After it downloads it says "some of the selected uopdates could not be expanded and verified. it may have been corrupted during download etc. The update will be download and checked next time " I have done this like 5 times in a row and the i get the same message. Since I am new to mac I have no idea how to debug this. Can someone tell me what I am supposed toi do now? Thanks. . Also if i uncheck all except one (like imove) I get the same message about the file being corrupted. When I check only tghe mac OS X update and it then asks to restart the computer, it again gives the message saying an unknown error has occurred and it couldnt be installed.