Closed game crash after uninstalling nightly

Recently, I installed the nightly version, and, after getting my fill of the cool stuff devs have planned for the stable, I decided to switch back. But ever since I have, I have been getting an error message like this at the beginning of the game when I click "launch Starbound" in the launcher:
So, finally, my question is: can anyone help, or has anyone had a similar issue they know how to fix? Any feedback is appreciated!

 

Delete your starbound.config file. The game will generate a new one that works with your build.

 

okay thanks