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PRB: E_FAIL Calling QueryInterface from an IUnknown Pointer Obtained from MAPIOBJECTProperty
Article ID: 296483 - View products that this article applies to.
This article was previously published under Q296483
When you query for a specific MAPI interface by using a pointer that you obtained from an Outlook object's MAPIOBJECT property, you may receive the following error message:
The MAPIOBJECT property is available only for compatibility with Microsoft Collaboration Data Objects (CDO) 1.21. It is a hidden property of Outlook Object Model objects, and is not meant to be used from the Outlook object. The MAPIOBJECT property is meant to be used from the corresponding CDO object.
To use the MAPIOBJECT property, use CDO to obtain it from the corresponding CDO object.
The following code sample uses the Outlook Object Model to demonstrate the problem:
The following code sample uses a CDO that allows proper access to the MAPIOBJECT property: