Lots of people face the problem where they cannot start Microsoft Outlook. There’s one error which gives you the following message each time you try launching the app: Cannot start Microsoft Office Outlook. Cannot open the Outlook window. This is annoying, especially if you get it while at the office, and you need to finish important work. Many people seem to think that this has something to do with the updates they installed on the system, but the underlying problem is usually something else altogether.

Corrupt Profile

There’s a file called profilename.xml, used for storing the navigation pane settings in the program. If something goes amiss with the data inside this file, it can cause problems with the application launch. In XP and Vista, this file is found in the respective paths: C: \Documents and Settings \Application Data \Microsoft \Outlook and C: \Users \AppData \Roaming \Microsoft \Outlook. Find the file and rename it. The next time Outlook launches, it will have created a new file instead of the one you renamed, and you should be able to start it up without any hassles.

Cached Exchange Mode

This might be the reason why you cannot start Microsoft Outlook. People usually use Exchange with Outlook in the office, to work on the server with others in the organization. The Cached Exchange Mode is what automatically stores local copies of your information, and this is convenient if you’re on a laptop. Turn off this feature if you don’t need it, and there’s a chance the launch error will disappear too.

ScanPST.exe

Maybe there’s something wrong with your PST file. This is the file that stores all of the personal information inside the application, locally. If there’s a corruption of the data in there, then the application itself won’t start normally, or at all. Use a PST repair tool to find and fix the issue. The native utility for this is Scanpst.exe. If this isn’t enough to fix your issue, then download a good third party tool for deeper scanning and more comprehensive resolution.

Make a New Profile

If it’s only your profile data that’s corrupted, and assuming it can’t be fixed, you’ll need to set up another profile so that you can start using Outlook again. But before doing this, backup the profile, in case you need it in the future for some reason. That way if you mange to fix the data corruption, you can always revert to the favored profile.