>How can I get it to resume.
Sorry I don't know. When update has gotten an error on me, that is the end of it in every case I recall. I don't even know how to get the update tray thingy to come back until it comes back on its own. Maybe that is what you want to know? Somebody ought to know that.
In the old days (before XP), I would search for a large, recent-date file in the IE cache when I lost a download, maybe having some bizzare, coded rename. Since the size of SP2 is over 250 M, it shouldn't be too hard to identify, if it is somewhere. (And it does have to be somewhere, doesn't it?) Maybe XP puts it in some other temporary folder, not the IE cache. Nowadays, I download the file itself directly with a resuming downloader (like the nice one at getright.com.) That way I know what is going on. ( I like that.) Besides being able to resume at a later date, or if the connection is lost, you can pause the download anytime you want, like when surfing gets too dang painfully slow. I have downloaded whole CD ISOs (650 M) over a period of several weeks.