Error message when you perform an action that opens a custom form in another user's mailbox in Outlook 2007: "The form you selected cannot be displayed"

You add another user's mailbox to your profile in Microsoft Office Outlook 2007. When you perform an action that opens a custom form in the other user's mailbox, the custom form does not open. Additionally, you receive the following error message:

To resolve this problem, apply hotfix 939596. After you apply the hotfix, you must clear the forms cache before you perform the action that opens the custom form in the other user's mailbox.

How to obtain the hotfix

This issue is fixed in the Outlook 2007 Hotfix Package that is dated June 29, 2007. For more information, click the following article number to view the article in the Microsoft Knowledge Base:

How to clear the forms cache

To clear the forms cache, follow these steps:

1. On the Tools menu, click Options, and then click the Other tab.
2. Click Advanced Options.
3. In the Advanced Options box, click Custom Forms.
4. In the Custom Forms box, click Manage Forms.
5. In the Forms Manager box, click Clear Cache.

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

For more information about how Outlook 2007 uses the forms cache, click the following article number to view the article in the Microsoft Knowledge Base: