Today, I would like to share some tips for troubleshooting issues with Microsoft Outlook. These tips will resolve 95% of all issues a person is having with Outlook. This article talks about issues with the Outlook offline cache, corrupt email signatures, and how to fix problems with offline Personal Folders. This information covers Outlook 2003 to 2010. Lets get started!

  • Install the latest Service Pack for your version of Microsoft Office.

Make sure that you have the latest Service Pack installed for your version of Microsoft Office. A Microsoft Service Pack is a major update for Microsoft software and include a great deal of bug fixes, security updates, and new functionality. There is a good chance that updating Office to the latest service pack will help resolve many of the issues someone is having, in addition to preventing future problems.

Office 2003, go here:

Office 2007, go here:

  • **Delete or Rename the Outlook cache file (OST).**In my experience, this step single-handedly resolves many of the support tickets that I work on Microsoft Outlook. Outlook stores email that has been syncronized with the email server in a database file with the file extension .OST. Force Outlook to recreate the file from scratch by renaming the old OST file or by deleting it. To do this:
  1. First, make sure Outlook is closed.

  2. If using Windows XP navigate to C:\Documents and Settings%USERNAME%\Local Settings\Application Data\Microsoft\Outlook. Or, if using Windows Vista or Windows 7 navigate to C:\Users%USERNAME%\AppData\Local\Microsoft\Outlook.

  3. Find the file that has the .OST file extension and rename it to something like “FILENAME.OST.BAK”, or just delete the file.

  4. Restart Outlook.

Outlook will recreate a new OST file.

  • Recreate Email Signatures from Scratch.

This is another one of those strange things that occurs between MS Word and Outlook. Recreate the email signature by creating a new one from scratch. DO NOT copy\paste from the old signature. Restart Outlook when you are done and attempt to send or reply to emails. If you don’t get any errors or formatting problems, then this was the cause of the problem.

  • **Convert your Personal Folders from 97-2002 version to the current plain PST version.**Ever had a problem trying to move emails to\from your Personal Folders and Outlook freezes up? The reason may be that the Personal Folders file (.PST) is the Office 97-2002 version, which has a 2GB storage limit. As you approach the 2GB limit, Outlook starts to ‘freak out’ and may crash. To fix, create a new Personal Folder (selecting the default PST option, NOT the 97-2002 option), then start moving emails from the old PST version to the new one.
  • **Use the SCANPST.EXE tool to fix a corrupt Personal Folder file (PST).**The second reason why you may have problems moving emails to\from your Personal Folders is because the PST is corrupt. Unfortunately, PSTs are insanely unstable and are susceptible to corruption. To fix a corrupt PST file, find the SCANPST.EXE tool using Windows Search and scan the PST file.

The default location PSTs are:

On Windows XP: C:\Documents and Settings%USERNAME%\Local Settings\Application Data\Microsoft\Outlook.

On Windows Vista or Windows 7: C:\Users%USERNAME%\AppData\Local\Microsoft\Outlook.