Hi,
Please help to confirm below information.
- Are RDSH, RDCB, RD Web Access, RDGW and RD Licensing installed on the same server?
- Have the certificate been installed for all RDCB, RD Web Access and RD Gateway roles and are they all trusted as below?
- Are both RDGW's internal and external names included in the SSL certificate?
- How you configured DNS so that external users can resolve the name of the RD Gateway to the right IP address?
Have you tried to ping the RDGW's external name on the test client to see if the test client can resolve the IP successfully?
Below is a blog about RDS Quick Start Deployment step by step. Please read it and follow the guidance to check if there is any problem in your environment.
https://nedimmehic.org/2017/02/08/how-to-install-remote-desktop-services-2016-quick-start-deployment/
Thanks,
Eleven
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