For the past few months, I’ve had a perplexing mystery in Outlook 2007. During an Outlook session, the first time I clicked the Actions menu item, I got four Microsoft Office Outlook OK boxes in succession. The first said:
The form region IPM.Note.Microsoft.Conversation.Region cannot be opened. The form region manifest specifies an add-in that is not installed.
Then I got three more, identical except for the region specified:
After that, the Actions button works fine. I got the same four OK boxes if I choose Tools®Forms®Choose Form. Again, after that happens, Choose Form worked normally. Either method of triggering the four OK boxes ended the problem for that session. Afterward, the error didn’t return unless Outlook was closed and reopened.
I Googled the problem, and found out the manifest is an XML file of some kind. But, a careful search of my system found no XML files containing anything like those. I asked for help in a forum where Outlook experts hang out… but, nobody had ever seen the problem before.
I tried renaming lots of XML files, just in case, but none fixed the problem. Starting Outlook in safe mode brought relief, but ultimately provided no help, as I disabled every add-in I have, as well as renamed my OutlookVBA.otm file. No joy.
Then, last night, a light bulb went off and I decided to start renaming registry keys in the Outlook tree. But, before I even got that far, I discovered the following in the registry:
And under it, I found:
…and the other three.
When I renamed …FormRegions as …FormRegions.x, the problem magically stopped. It turns out that the cryptic error message was right on target. The only problem was that it failed to tell me what the @#? the “form region manifest” actually was. In truth, I’m still not sure, only that removing the reference from the registry made the problem go away.
My only guess as to how this happened is that I must have installed and removed a long-forgotten add-in (i.e., “an add-in that is not installed”) at one point, and the removal program failed to clean up after itself when it departed. I just love mysteries with happy endings.