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Interop.Outlook._Application

Interface not registered (Exception from HRESULT: 0x80040155) – Microsoft Office/Outlook Error

If you recently uninstalled Outlook 2013 or Outlook 2016 or have a problem with your Outlook installation then you may encounter the following error messages:

Unable to cast COM object of type ‘Microsoft.Office.Interop.Outlook.ApplicationClass’ to interface type ‘Microsoft.Office.Interop.Outlook._Application’.

Read More »Interface not registered (Exception from HRESULT: 0x80040155) – Microsoft Office/Outlook Error