You may receive a "Run-time error '13': Type mismatch" error message when you try to programmatically open an encrypted e-mail message in Outlook 2003

When you programmatically use the Microsoft Outlook object model to open an encrypted e-mail message in Microsoft Office Outlook 2003, the e-mail message does not open. Additionally, you may receive the following error message:

This problem was first fixed in a hotfix that is now contained in a service pack. If you installed the latest Office 2003 service pack, you do not have to install the hotfix.

Service pack information

This problem is corrected in Office 2003 Service Pack 2.

To resolve this problem, obtain the latest service pack for Office 2003. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

After you install the service pack, follow the steps that are listed in the "More Information" section of this article to set the AllowOMWithUI registry key and to activate the hotfix.

Hotfix information

How to obtain the hotfix

This issue is fixed in the Outlook 2003 post-Service Pack 1 Hotfix Package that is dated March 28, 2005. For more information, click the following article number to view the article in the Microsoft Knowledge Base: After you install this hotfix, follow the steps that are listed in the "More Information" section of this article to set the AllowOMWithUI registry key and to activate the hotfix..

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Office 2003 Service Pack 2.

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:
To activate this hotfix, follow these steps:

1. Quit Outlook 2003.
2. Click Start, click Run, type regedit, and then click OK.
3. Locate and then click to select the following registry key:
   HKEY_CURRENT_USER\Software\Microsoft\Office\11.0\Outlook\Security
4. After you select the key that is specified in step 3, point to New on the Edit menu, and then click DWORD Value.
5. Type AllowOMWithUI, and then press ENTER.
6. Right-click AllowOMWithUI, and then click Modify.
7. In the Value data box, type 1, and then click OK.
8. On the File menu, click Exit to quit Registry Editor.