You cannot accept an invitation that is in a third-party calendar format in Outlook 2007

Consider the following scenario. In Microsoft Office Outlook 2007, you receive an invitation to a meeting. The invitation is in a third-party calendar format. For example, the invitation is in the Apple iCal format. In this scenario, you cannot accept the invitation.

How to obtain the hotfix

This issue is fixed in the Outlook 2007 post-Service Pack 1 Hotfix Package that was released on January 28, 2008. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

Registry information

Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

After you apply this hotfix, you must modify the registry. To do this, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate and then click the following registry key:
   HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Outlook\Options\Calendar
3. On the Edit menu, point to New, and then click DWORD Value.
4. Type ExtractOrganizedMeetings, and then press ENTER.
5. On the Edit menu, click Modify.
6. Type 1, and then click OK.
7. Exit Registry Editor.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.