Try to run docker ps and check if all of your clearml containers up and running (should be 8 total)

yes. all 8 of them are running

The server usually takes about 2-3 minutes to start up (ES takes time to warm up), does the issue still affect you?

SucculentCrab55 I've had this problem when I tried to launch UI too quickly, try to wait a bit and then check UI again

@<1526734383564722176:profile|BoredBat47> I've tried it multiple times. still doesn't work

I encountered a similar event when I installed ClearML on Ubuntu set up on WSL2.
In my case, the cause was probably that I had limit on the memory allocated to WSL2 (up to 2 GB) by editing the .wslconfig file.
It seems that elasticsearch cannot start properly if the memory is low.
By removing the restriction, the WebUI was displayed.
A similar environment might solve the problem.