You have enabled the reading pane in Microsoft Office Outlook 2007. However, when you select an e-mail message that is restricted by Information Rights Management (IRM), Outlook may stop responding. This article helps you fix the problem.
To resolve this issue apply hotfix 960535.
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
960535 Description of the Outlook 2007 hotfix package (Mso.msp, Outlook.msp): December 16, 2008
After you apply this hotfix you must set the DisableDrmErrorCachingWithOM registry entry.
Important This section, method, or task 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. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:
322756 How to back up and restore the registry in Windows
To resolve this issue, follow these steps to set the DisableDrmErrorCachingWithOM registry entry:
Click Start, and then click Run.
Type regedit, and then click OK.
Locate and then click the following registry subkey: