I have and RDS environment based on Windows Server 2019.
I have an RD Gateway, RD Connection Broker and RD Session Host.
Users' profiles are stored on user profile disks and UPD vhdx files are stored on RD Connection Broker server.
Not sure when exactly Start Menu and Search functionality stopped working (at very least more than a month ago) but now when I click on Start button or try to use Search nothing happens.
Start button only responds for Administrator account (not any user in Administrators group but Administrator account only).
I found this article https://www.phy2vir.com/windows-server-2016-2019-rds-server-black-screen-or-start-menu-not-working/ and tried to run the script that removes all firewall rules except unique one that don't have an owner.
The script successfully removed more than 32000 firewall rules but unfortunately didn't resolve my issue with Start button.
If someone had this issue with RDS environment + UPD and was able to fix it please share your knowledge.