Try restarting it with the following commands:
Run commands in cmd. ctrl+r > type cmd >click OK > enter the commands below at prompt window.
net stop BITS
net start BITS
I f that doesn't work, then try deleting the Downloader folder. Do this in the following manner browse to the network folder : C:\Documents and Settings\All Users\Application Data\Microsoft\Network.
Do not delete the network folder The Downloader folder is what we want. Within the downloader folder are two files that BITS uses qmgr0.dat and qmgr1.dat, we want to see if BITS wil recreate these files.
If you are able to delete the downloader folder that means BITS wasn't functioning properly. The folder should be automatically recreated, and your updates should install. If BITS is running properly then you should receive this error message (see attachment).
If by any chance after you've deleted the downloader folder, and it Isn't recreated you can simply restore it from the recycle bin.
let me know how this turns out.