Overview
Outlook plugin fails to connect and the debug logs are showing the following error in the OutlookAddInCore log:
OutlookAddInCore", "Error: Failure whilst performing Web Service Version with error: System.ServiceModel.ProtocolException: The remote server returned an unexpected response: (400) Bad Request. ---> System.Net.WebException: The remote server returned an error: (400) Bad Request.
Environment
- GFI MailEssentials
- Outlook plugin
- All supported environments
Root Cause
HTTP redirect in Internet Information Services (IIS) is not allowing the authentication to occur with the MailEssentials_Service. Disabling the redirect allows the connection to complete.
Resolution
- Open the IIS Manager.
- Locate the website with the MailEssentials_Service Virtual Directory.
- Select the HTTP Redirect.
- Uncheck the redirect if applicable.
- Perform an IIS reset and retest the connection.