I can't get the launcher to work
The most common reason you'll get this error is if your web browser has an ad blocker, like Pi-Hole, which is preventing the launcher from using your browser. The launcher needs to access the internet to confirm it's you wanting to access your account.
Add our authentication url to your ad blockers or other firewalls
Whitelisting mpsnare.iesnare.com with your ad blocker should solve your problem. If you have other security settings that limit access to the internet you may need to whitelist our url there.
Run a clean boot/clean startup
If this doesn't work, or you're not sure how many ad blockers you're using or where they live, a clean boot will start your computer with a minimal set of drivers and startup programs. That should let you see if software, like an ad blocker, is preventing you from running your game. Microsoft has step by step instructions to show you how.