Azure AD Proxy cert not auto renewing

Make sure your Azure AD proxy is the latest version and update to latest version if it isn’t. Since mid 2017 the app auto updates.

If that doesn’t update the cert try this in powershell:

Import-module AppProxyPSModule

Register-AppProxyConnector

You will be prompted for a feature enter “ApplicationProxy” (no quotes).

Of course do this at your own risk, take backup’s snaps etc.