Last Saturday (08/21/2021) I was contacted by the company I work. What happens is that an incident where some users were getting an error screen below:
The solution's dashboard did not indicate an abnormal situation in the components, nor did we have alarms triggered by the monitored processes. The error situation was only occurring on one connection server and was intermittent. Referring to RFC the HTTP error code 599 is as “unassigned”. Searching the Internet, I found nothing either. You can be sure this is the first post on the planet with the hashtags #vmware #horizon #http #error #599.
Notice in this post how difficult it is to diagnose. Solution, power off/power on on the server and life that follows.
The Error you are getting while connecting to Horizon from internal network or external network