Welcome to the SeeMeCNC Community

Ok... please forgive me because I had this problem once before; solved it; but can't remember what I did....

Just installed my new E3D hotend and went to update Config.H on Repeteir.ino (Arduino 1.0.5r2). Can't get it to upload after is compiles. Have USB connected; Arduino shows its on Com4. However, keep getting a message "Com4 port aleady in use" when I compile. This seems to be a Mac headache. Running Windows 7 on the Mac via Parallels. Have successfully done this before... can't remember how! And I am very excited about this E3D and can't wait to fire this guy up!

Any help would be appreciated.

Dave

Why are you running Arduino in parallels? Its a problems with your VM setup probably. Just download Arduino for OS X and upload your firmware with that. Probably easier to do it that way than to diagnose and fix a VM problem.