To put this another way, when Office is reinstalled, Outlook will continue to use the existing Outlook profiles. When Office/Outlook is uninstalled using Control Panel, the existing Outlook profiles are not removed and persist. Uninstalling the apps listed here and repairing Office didn't help, but running the latest batch of updates that came out on Tuesday 14th February 2012 seems to have fixed the issue.In terms of correcting errors occurring within Outlook, there are times when performing an uninstall/reinstall serves no purpose and is a complete waste of time. We encountered the same issue again with another machine. This issue now appears to have been solved with a Windows Update. I think the conflict was with 'Visual Studio 2005 Tools for Office Second Edition Runtime', though I've no idea which application installed this in the first place. I've since reinstalled Zetafax Client Applications and Microsoft Silverlight with all the latest Windows Updates and Excel is still working. I then performed yet another repair on Office Home and Business 2010, rebooted and voila - Excel is working again.

Visual Studio 2005 Tools for Office Second Edition Runtime

Just when I thought I was going to have to wipe the computer and reinstall everything to fix the problem, I decided to uninstall applications one at a time to see if one was conflicting.

Office 2010 removal tool