Unable to install games on the XBOX App in Windows 10?

Problem: You get the following error message: Error 0x80073D26 or 0x00000001 occurs when you try to install, update, or launch a game on a Windows 10 device.

Solution: Update Windows.

More detail: no, seriously. Update Windows. I spent an hour on this before finding a helpful solution and I would like to save you the trouble.

Why does this happen: Something failed in the the most recent Windows update of the Xbox Gaming Service, and your folders no longer have permission to do… anything. Taking control doesn’t work, restarting your computer does not work, deleting folders doesn’t work, uninstalling/reset does not work. Searching for the relevant error codes does not immediately lead to the correct KB article, so hopefully this will help direct you to update your Windows install with the optional update KB5004476 which does work.

Happy gaming!