Payday 3 has had its fair share of errors and server problems, whether it's not letting players launch heists or simply not letting them log in whatsoever; multiple errors such as the Nebula Data Error or the Nebula Connection Error may prevent you from authenticating to the game. I'll tell you what they are all about below and how to fix them.
Nebula data error - Failed to fetch game config data solution (Payday 3)
If you've logged in to Payday 3 and have seen an error not letting you log in, you're not the only one. Payday 3 servers have been facing a lot of problems—perhaps due to the number of players who are trying to all connect at the same time.
The first thing you'll want to do is check if this problem is on your side or the server side. You can do by staying up-to-date with the game's social media platforms (like X / Twitter) or reddit, since the developers are quick to notify players there of any ongoing technical issues.
Related: How to link your Steam to your Nebula account in Payday 3
If the developers or your fellow players haven't reported anything of this nature, you can try to restart the game or return to login, making the game re-authenticate you. If none of this really works for you, then there are a few key things to keep in mind, such as if this is your first time launching Payday 3, or if you've gotten this error all of a sudden after playing normally; if so, then you should check if you changed any settings.
Nebula Connection Error solution (Payday 3)
You can check if your firewall, antivirus, or DNS settings aren't stopping the game from connecting, then try again. In short, however, this problem is almost always on the game's side, so the best thing you can do is wait it out.
For more on Payday 3 error fixes, be sure to check out How to Fix Payday 3 Network Error (No Network Connection) here on Pro Game Guides.