If anyone else, like me, has been stuck on “Nat Type - Moderate” forever for Xbox Live (Windows 10), I finally found a fix. Ever since I got Gears 4 at launch, it annoyed me that it always showed up as “Moderate” in the Xbox App for me. I tried opening ports and messing with command prompt in the past, but it never worked.
Finally, I got it to Open a few minutes ago. Here’s what did it:
Source ~ https://www.reddit.com/r/Windows10/comments/9lh28u/how_to_fix_teredo_is_unable_to_qualify_issue_in/
Source ~ https://answers.microsoft.com/en-us/windows/forum/apps_windows_10-win_xbox/xbox-app-say-nat-type-open-but-server-conectivity/b53270b2-ceb7-4063-a5af-d77b82e23e2a
After trying port forwarding and other instructions on how to uninstall/reinstall Teredo and mess with it’s settings in Command Prompt from Gears 4’s launch until like 2018, I gave up. I only messed with it now because I noticed sometimes when I checked the Network since reinstalling Gears 4 about 2 weeks ago, it would give a message about “Teredo is not able to qualify”, then it’d fix itself after checking Network again.
So I wanted to just get rid of the issue. I got it working, then for the hell of it decided to try one more time to get “Open” Nat Type, expecting it to not work ofcourse. Well, it worked!
Anyways, anyone else stuck on “Strict” or “Moderate” Nat Type, I hope this can help you.