Server inaccessible from localhost, local ip and Tailscale?

[unleashed7]

I cannot connect to the server from localhost:8096 or Tailscale IP only 127.0.0.1:8096. I'm not good with networking, but isn't 127.0.0.1 supposed to be the same as localhost?

Doesn't work:
- localhost:8096
- [tailscale ip]:8096
- 192.168.0.20:8096 (PC ip)

Works:
- 127.0.0.1:8096
- [public IP]:8096

This happened when installing a new windows, all 3 in including Tailscale worked fine before. Any tips how to fix it?

[unleashed7]

I added the port 8096 as incoming rule to the firewall, that didn't help.

Also figured out, pinging localhost resolves to ::1 for some reason, not sure if this is the problem. Tried adding 127.0.0.1 localhost to the hosts file, didn't help.

Tried accessing the server from an outside network through Tailscale IP and funny enough, it worked. So it must be a local issue, but I have no idea how to fix it.

I hate networking so much...