There are two possibilities - the relevant bit of the code is...
EDIT: Out of curiosity - this uses the same code, do you have the same problem when installing it?If Listed Then 'check this addins checkbox in the addin dialog box AddIns(AddinTitle).Installed = True Else 'it's not listed (not previously installed) 'add it to the addins collection 'and check this addins checkbox AddIns.Add(ThisWorkbook.FullName, True) _ .Installed = True End If