This works for me:
Code:
Sub KillMyAddin(sAddInFileName As String)
Dim strFile As String, oAddIn As AddIn
For Each oAddIn In Application.AddIns
With oAddIn
If .Name = sAddInFileName Then
strFile = .Path & "\" & sAddInFileName
.Installed = False
.Delete
End If
Kill strFile
End With
Next
End Sub
One thing to note though is that, if the Addin is also the attached template, you'd have to detach it (e.g. ActiveDocument.AttachedTemplate = "") before you could delete it.