Connecting to Printrbot

I have a PrintrBot Simple metal and have been using Repetier Host for over a year now, but every time I connect to a new computer for the first time, I run into a few problems every time. 

This time I reinstalled Repetier Host, the divers and got it to connect using COM1 and a Baud rate of 56000, but then I get the "No start signal detected - forcing start" message and nothing happends. 

I read that this means I need to set the "reset on disconnect" to disabled, but I can't find that setting anywhere.

Any help or suggestions?

Thanks

keegan