Application Load Balancer getting 502 bad gateway error with Windows Server 2022

Question

My ALB was working correctly with a windows server 2012 EC2 instance.  When I changed the target to Server 2022, it immediately started getting the 502 bad gateway error.  The error comes back immediately.  The health check works using HTTP.  All HTTP traffic works as expected.  When I introduce HTTPS traffic, that is when I get the 502 error. I have gone through all the troubleshooting steps I can find.  It is related to server 2022 somehow, but I am not sure what to check next.

Answer

Thank you, Gary.  I appreciate your help.  The service (website) does work locally, and from the outside.  It just does not work through the ALB.  I have checked and re-checked the security groups numerous times.  The same policy that allows http (80) also allows https (443).  
I need to make one correction to my original post.  The EC2 instance is Windows Server 2022, if that makes a difference.

Answer

If you’re on the server locally. Does https://127.0.0.1 work?

If not you will need to setup an ssl cert.

If it does you’d need to check the ALB and EC2 security groups to allow https.

Answer

I have been able to confirm that the ALB is getting a TCP RST from the windows 2022 server for HTTPS requests.  I just don't know why.  The troubleshooting articles just says, " load balancer can't establish a TCP 3-way handshake with the target".

Application Load Balancer getting 502 bad gateway error with Windows Server 2022

Relevant content