The ADFS won’t start for unknown reason and I got this error message when I looked at the event viewer:

The Active Directory Federation Services service terminated with the following error:

An exception occurred in the service when handling the control request as shown in the image below.

The error message is seems to be generic exception message without any further details provided. After a quick research and looking around at the event viewer, I found more descriptive error message on: Applications and Services Log>AD FS>Admin

The error message described the connection to SQL could not be established, as my practice ADFS setup is using internal database, it turned out to be the Windows Internal Database service is stopped.

Fix :

Open services.msc, search for windows internal database and start the service.Once you’ll find the windows internal database service is up and running, Finally start the ADFS service again, which should start successfully without any issues. Best of luck 🙂