This error usually indicates that the Outlook profile is corrupted. To resolve the issue, follow the troubleshooting steps below and check whether the Outlook profile works normally after each step.

We strongly recommend that you back up Outlook data prior to making any changes. There could be some messages stored only on the local machine and not synchronized with the server due to Outlook profile corruption.
Read the Knowledge Base article on How to export data in Outlook for instructions on exporting data to make a backup copy.

Troubleshooting:

  1. Start Outlook in online mode.
    Disable Cached Exchange Mode for the Outlook Exchange account and restart Outlook.
    You can disable Cached Mode in File (Tools) > Account Settings > double-click on the profile name > uncheck Use Cached Exchange Mode, save the changes and restart Outlook. Read the Knowledge Base article How To Enable Cached Exchange Mode In Outlook for more information. .  
      • You can recreate the profile.
      • You can find the OST file and rename it. Start Outlook and let the OST file be rebuilt. Read the Knowledge Base article Outlook Data File Locations.

    If you see that synchronization started successfully, enable Cached Exchange Mode again and restart Outlook for the changes to take effect. You can compare the mailbox on the server and the mailbox in your Outlook by using Outlook Web Access.
    Read the Knowledge Base article on How to enable Cached Exchange Mode in Outlook for detailed instructions.
  2. Make sure that there are no conflicting profiles in Outlook.
    Navigate to StartControl Panel > Mail*. Click Show Profiles. Verify that you need all the profiles that are listed. If you see duplicate profiles, remove them. Then restart Outlook.
    Note: You may want to back up profiles before deleting. To do this, log in using the profile you intend to back up, and follow the instructions in the Knowledge Base article on How to export data in Outlook.
  3. Re-create your Exchange profile.
    1. Navigate to StartControl Panel > Mail*.
    2. Click Show Profiles. Select your existing Exchange profile and click Remove.
    3. Now create a new profile and start Outlook.
      You can do this automatically or manually. To use Outlook Profile Helper to create the profile, download the application from HostPilot > Get Started Here! > Step 2 > Download Profile Helper, run it and complete the wizard, then start Outlook.
  4. Sometimes when creating a new profile doesn't help, the only solution is to re-install Outlook. Please make sure that you have backups of all the data from all Outlook profiles. Also note that if you had other profiles, you will need to configure them from the begining when Outlook is re-installed. When Outlook is installed, run Outlook Profile Helper to configure a new profile.

Tip: If you cannot locate the Mail icon within your Windows Control Panel, try the following steps:

  • On the left side of Windows Control Panel, select Classic View
  • If you still can't find Mail, look for it under Show 32-bit Control Panel Items.