"Access is denied" error when starting the Web Management Service

The Web Management Service will fail to start with a "Code 5" error in the console and an "Access Denied" event in the Windows security logs if you have the Block untrusted fonts policy enabled. This is a known issue that has been fixed as of build 1903.

Here's the Microsoft Tech Community post from a Microsoft support escalation engineer that solved this exact problem for me. https://techcommunity.microsoft.com/t5/iis-support-blog/wmsvc-web-management-service-failing-to-start-with-quot-access/ba-p/770603

It is likely that the block untrusted fonts setting is enabled on your server either by registry, local policy, or domain-based group policy. In my environment, I created a policy that only applies to Windows Server 2019 machines and disabled the following setting:

Computer Settings > Administrative Templates > System > Mitigation Settings > Untrusted Font Blocking

After running gpupdate and rebooting, the service started successfully.