I keep getting an error with the unreal ART toolkit

Whenever I click build control rig I get this.

Fatal Error. Attempting to save in "C:/Users/Username/Local/Temp/username.2015109.1534.ma

I can’t figure out why

Edit: It doesn’t work whenever I have a chain joint called ponytail. (I’m following the video tutorial) when I remove the chain joint everything runs smoothly. Why would this be? thanks in Advance

Try temporarily deleting or renaming your Preferences folder for Maya and rebuilding the rig. With a clean Preferences folder it might work.