I’ve tried logging off/on in XBox App and restarting the computer.
Looking on the web, there are so many posts with different solutions, it’s too confusing. On the forum, previous posts concern logging into XBox Live. Looking at the XBox networking settings, it says
0x80004005 is a generic Windows error that is often related to Windows Update. You can try to work through this list. Maybe some of it will help you: How to Fix Error Code 0x80004005
Judging by your last screenshot of the Xbox network test you either have a network hardware configuration issue or a router with an extremely hardened firewall rules configuration. You have an issue with IPv6. Teredo is a transition technology that gives full IPv6 connectivity for IPv6-capable hosts that are on the IPv4 Internet but have no native connection to an IPv6 network.
Is windows update running just fine?
You may try the following in this order.
Firstly, verify that your network hardware on your PC is configured properly with the following items, specifically the IPv6 protocol.
If it isn’t listed in there then I would recommend you uninstall your network drivers. Even if it is, it might be worth it to do, because this would insure all is reconfigured to defaults including any settings that may have become corrupted or changed for some reason or the other. Before you do, make sure to download the latest network drivers for your motherboard/network card if you’re by chance using a network card and not the network connection built into your motherboard. You may find these drivers for your network hardware on the Motherboard manufactures website. Uninstall your current network drivers, reboot your PC then reinstall the network drivers for your network hardware on your PC, reboot your PC. Any time you uninstall software from your PC and especially drivers, it is important to reboot the PC, then upon installing software and especially drivers, reboot the PC. Always the protocol, Uninstall = Reboot, Install = Reboot.
Try resetting your windows firewall rules back to default. Restart your PC then try to launch the game. It will/should prompt you to allow the game through the software firewall. When it does, select both network type boxes and click OK
If the problem still persists then I would recommend you contact your ISP and tell them that you are having issues connecting to certain services online and then they could go from there with taking a look at your router settings. By chance has anyone recently performed a reset on your router? Not a power-cycle but a reset? Resetting is different from power cycling, when there is a router rest it erases the settings stored in the router and could result in loss of connectivity if you had certain port forwarding configurations deleted during a reset.
Thanks for the suggestions. Eventually, the problem was actually solved by running in Administrator Mode! Not only this problem but two others were also solved.
I can’t see why this should work, but it seems to work consistently. All I can think is that my computer needs Administrator Mode to run some of the support apps, but why it’s been working since the sim was released, only going wrong over the past few months is certainly a mystery.