Seen a ton of you getting the langfix.exe error, and just wanted to help you guys out a bit. This is the same fix for "D'oh, this isn't good an error has occured: Unable to load language [en]" on other clients.
Method 1 (Windows only*):
1. Go to MPGH
2. Go to RotMG Hack Section
3. Download the langfix.exe
4. Run the langfix.exe
5. ???
6. Profit xd
Method 2:
1. If you're on Windows, open Control Panel. If you're on mac, open System Preferences
2. Go to the flash player option. If it's not on the starting screen, search for it in the search bar.

3. Go to the Advanced tab
4. Open the Trusted Locations Settings...

5. Locate the .swf of your RotMG Hacked Client and add it to the list of Trusted Locations.
6. Restart your flash player and it should be fixed!
Hope this helps lel
*Method 1 is Windows only because Macs can't open .exe files
