I have CRM 2016 rollup 1 front server with ADFS 3.0  in the same box windows 2012 with two backend servers that runing the async and sanbox services.

Recently we was not able to run outlook clients or connect to xrmtoolbox.

When I checked https://sts2.company.com/adfs/services/trust/mex I get 503 error.The CRM users are able to login normally to CRM.

The event viewer shows event id 102 

There was an error in enabling endpoints of Federation Service. Fix configuration errors using PowerShell cmdlets and restart the Federation Service.

Additional Data
Exception details:
System.ServiceModel.AddressAlreadyInUseException: There is already a listener on IP endpoint

I'm confused because the connection to outlook clients and xrmtoolbox was working even with this event log was present.

Many blogs suggest to change the tcp port of the adfs using powershell command Set-ADFSProperties -nettcpport 809

I need confirmation is this is the right solution?

Thank You