Outlook add-in is not loading

I had a Windows 8 Danish and Office Pro 2013 English installed on my computer. I am using a plugin for Outlook, Harmon.ie. All worked perfect. However after installing Windows 8.1 pro Danish and installing Office 2013 from Office 365, Outlook do not load the Harmon.ie add-in. I have talked to Harmon.ie support. However after trying many things they concluded that it is a Microsoft issue.

This mean I am stock!

This is the error I get from the Harmon.ie log

2013-10-07 16:13:00,417 ERROR [1] Mainsoft.Harmony.AddIn.HarmonyAddIn - Exception on Init

System.MissingMethodException: Metoden blev ikke fundet: 'Microsoft.Office.Core.LanguageSettings Microsoft.Office.Interop.Outlook._Application.get_LanguageSettings()'.ved Mainsoft.Harmony.AddIn.HarmonyAddIn.SetUILanguage() ved Mainsoft.Harmony.AddIn.HarmonyAddIn.Init()

The supporter from Harmon sais the following:

"It appears Harmon.ie is correctly installed and registered.Outlook does not remove or disable it but a failure occurs during the loading stage when calling Microsoft.Office.Interop.Outlook._Application.get_LanguageSettings"

Please advise, I am stock!!!

Have you asked Harmony whether they have tested the combination you have been using?

How has it been determined that it is a Microsoft problem?

Thanks

Rob