Error using VSTO 2005 Outlook Addin with VS2005 RC1
Just installed Visual Studio 2005 RC1 and reinstalled Visual Studio Tools for Office 2005 Outlook on top to continue working on my Outlook Add-in. When trying to cast a MailItem object i recieved the following error:
System.InvalidCastException: Unable to cast COM object of type 'System.__ComObject' to interface type 'Microsoft.Office.Interop.Outlook.MailItem'. This operation failed because the QueryInterface call on the COM component for the interface with IID '{00063034-0000-0000-C000-000000000046}' failed due to the following error: No such interface supported (Exception from HRESULT: 0x80004002 (E_NOINTERFACE))..
Seems like something didn't register properly and after performing the following operation from the Visual Studio 2005 Command Prompt (in a folder containing the dll) I was back up and running:
regasm Microsoft.Office.Interop.Outlook.dll