Option1:

To resolve the problem, you can take the following steps:

• Open Outlook.
• Click on Help -> About Microsoft Outlook.
• Click on the Disabled Items button.
• You will see a Disabled Items window open, with the following information within it:

The items below were disabled because they prevented Outlook from functioning correctly.

Please note that you may have to restart Outlook for these changes to take place.

Select the ones you wish to re-enable.

If you see "Addin: outex.dll (outex.dll)" listed, click on it to highlight it and then click on the Enable button. Then click on the Close button. Then click on the OK button to close the About Microsoft Office Outlook window.

Option2:

Important - This method contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs

Try removing the following registry key:

• Click Start, and then click Run.
• Type regedit, and then click OK.
• Navigate to the following key and delete it:
  HKEY_CURRENT_USER\SOFTWARE\MICROSOFT\OFFICE\11.0\OUTLOOK\Resiliency