Unable to write to config directory. Please make sure you have permissions for your Klei safe folder.

Generally, the "unable to write to config directory" error happens because something on the computer is blocking the game (or the Steam client) from being able to read/write/access your hard drive, specifically the Documents folder, where important game save and server files are located. 

If you have not done so yet, please follow the steps in our troubleshooting guide: https://support.klei.com/hc/en-us/articles/360029882171