TMG Web Listener Certificate "Private Key handle error" 0x80090016

You may face an issue with a certificate assigned to a listener that suddenly becomes invalid and therefore the incoming SSL connection are dropped. Restarting the service you will show the following error: Event Source: Microsoft Firewall Event ID: 14060 Description: Description: Cannot load an application filter Web Proxy Filter ({4CB7513E-220E-4C20-815A-B67BAA295FF4}). FilterInit failed with code…