After applying Update Rollup 2 for Exchange Server 2007 Service Pack 3 (KB2407025) last night, we had an issue that took out Outlook Web Access aka OWA. Users logging into OWA via Internet Explorer got a blank page. Logging in from other browsers worked, but the pages were devoid of any CSS styling or images.

The problem was due to the fact that the update initially failed upon install. When it did, the IIS service was not restarted. On the next attempt to install the Rollup the process completed, but the processes finalizing OWA updates were skipped.

Turns out this is not such a rare occurrence, but most solutions have seem to involve uninstalling / reinstalling IIS as well as the CAS role. Yuck! Luckily there is far less invasive solution to try in the form of a built in PowerShell script. On the affected server, open up the Exchange Management Shell (aka EMS) and run the following script:

C:\Program Files\Microsoft\Exchange Server\Bin\UpdateOwa.ps1

The script will go and try to clean up after the botched OWA update. No uninstall / reinstall chicanery required. For more information, check out the following threads: