So I have been pulling my hair about an issue: I'm trying to install openAM on my machine but it complained about not being able to bind to port 50389. netstat -aon | findstr 50389 returns empty line, indicating that the port in question is actually not used by any process. Digging around, I found this stackoverflow post about being unable to bind to port, tho that port is unused. In short, Windows let programs to reserve a range of ports while not using them, to prevent other programs to use that range. To tell which ports are reserved, you can run netsh int ip show excludedportrange protocol=tcp. To try to free port range: netsh int ip delete excludedportrange protocol=tcp numberofports=100 startport=49909. If you got Access Denied, it probably means the process reserving that port is currently running.

The author of the post thought turning off Hyper-V would release the reserved ports. I tried that and it worked in my case.