Run - time error -2147467259

I wrote an outlook addin which adds a toolbar to the email message when its openened. It's working fine. However when the user changes the properties of outlook to "Use Microsoft word to edit e-mail messages" the code breaks out with the following error:
RUntime error -2147467259 (80004005)
Object Variable or with Block variable not set
THe line that it errors out on is:

VB Code:

Set myCommandbar = myInspector.CommandBars.Add("AddinBarI")

I thinks it has something to do with the fact that it is bringing in the word toolbar...
ANy ideas..
Thanks

VB Code:

Dim objOutlookApp As Outlook.Application
Dim cmdbrNewCmdBar as commandbar
 
Set objOutlookApp = New Outlook.Application
 
If not (objOutlookApp is nothing) then
    Set cmdbrNewCmdBar = objOutlookApp.ActiveExplorer.CommandBars.Add("Menu Bar")
End If

There's a little more on this one over at this site:
http://msdn.microsoft.com/library/de...ainoutlook.asp