[FIXED] An unknown I/O error has occurred

[Bio-Mech]

What's Happening

After you click "Play" from the Super Motherload Launcher, the game launches and then immediate displays an error dialog with the message "an unknown I/O error has occurred".

What's Really Hapening

Upon launching, the game attempts to create the Common Save Data files. These files contain the upgrades for all characters in both Normal and Hard Core mode, as well as user preferences, and the save data is shared across every world you create. The game wasn't successful creating those files and cannot proceed until it can.

Possible Reasons

You have an older version of the game

Issues with accented Windows usernames have been solved in the latest version of the game (1.4.0). Steam will update Super Motherload automatically if you have not disabled Steam updates.

[ChaoticBoredom]

This should be fixed as of version 1.4.0, made live today.