Recent Windows security update KB4550929 causes Horizon Connection servers to go into an error state "The service is not working properly." We ran through recommended troubleshooting (https://kb.vmware.com/s/article/2135462) for that error and confirmed the following:
- Ports 80 and 443 are not in use by another program
- Replication is still functioning among Horizon Connection servers
- We do not have a view composer installed
- SSL certificate is valid
Another symptom is connection refused when accessing the localhost Horizon 7 Administrator Console through a web browser.
Uninstalling the update resolves the issue.
