"Contacting Server. Connecting to transport service. Please Wait." - Unable to play multiplayer

[Daniel]

When I try to use online features, a message saying "Contacting Server. Connecting to transport service. Please Wait."

I can't get any further and as a result can't play multiplayer. Has anyone else had this before?

[lukie-luke]

Recently this has started happening to me after working fine for months. My game has also started freezing after I click "Quit to Desktop" and can only be closed via Steam or Task Manager. My friends are currently playing with no problem, and it works for me on my old laptop connected to the same router. Halo Infinite works fine tho. I have done everything I can think of with no luck. Here are some things I've tried:

- Uninstall / Reinstall - including cache files, etc.
- Verify game file integrity
- Log out of account (in game and xbox game bar)
- Turned off in game relays
- Uninstall / reinstall NordVpn - also tried with or without VPN connection
- Try Wifi / Ethernet
- Cleared DNS cache
- Changed to CloudFlare DNS server
- Uninstall latest windows 11 update
- Manually get updates from Microsoft Store
- Reboot router
- Factory reset router and change security settings

Other steam games work for me, but Sea of Thieves on the Microsoft Store also does not connect so I'm wondering if it has something to do with Microsoft servers, but there is absolutely no reason for this issue to be happening all of the sudden.