How to diagnose why an update cannot be installed on Windows Server 2003?

Solution 1:

Assuming it's just some, and not all... then you'll need to post an error number/message to get some information.

If it's all, then try re-registering the windows installer service

msiexec /unregister
msiexec /regserver

For Agent WARNING: LoadLibrary failed for srclient.dll with hr:8007007e - have a look at KB831429

Solution 2:

Have a look at %systemroot%\windowsupdate.log

You can also check Event Viewer.

Microsoft's general troubleshooting guide for updates can be found here.

Solution 3:

Remember also [for XP and before, see below]that each individual update has its own log file in the Windows directory. This will be, usually, named KBnnnnnn.log where n is the update number. The update failure will usually be in the Event Log but the details will be in that log file.

Vista and 2008 have changed this logging but I don't remember the details. I'll edit it again if I find it.

Also, for anyone watching the progress bar in Windows Update stalling, this phenomenon is unfortunately normal for some updates; the Malware Removal Tool actually scans your directories (which would uncover the RAID problems the original poster had.) Exchange updates like to take their time as well as they stop and start all the services as they run.