Cannot start Microsoft Office Outlook. Cannot open the Outlook window

I was told by a user today that he experienced an error in Outlook "Cannot start Microsoft Office Outlook. Cannot open the Outlook window." I checked with what he'd done before this problem, it's because that he didn't shut down the system properly, i.e. forced shutdown with power button while Outlook was still running.

I googled and found an article (available at here) discussing the same issue. The problem was resolved after running the command in Start -> run -> enter "outlook /resetnavpane"

Actually there are other commands/switches available in Outlook to address different issues, you may access to the following link to see what each one of them do.
http://www.outlook-tips.net/howto/commandlines.htm

Cheers...