Connection failed com 1 is denied???
Check in device manager what com port your printer has.
Please select the proper com port in the software
Did that its in com 1 but wont apply when clicked on??
Just to make sure this is the correct com port.
Open device manager expand “ports com and LPT”
When you unplug the printer from the USB port does com 1 go away?
Had the same issue and it was (I think) because the port was claimed by the Repetier server, after stopping the server (from the start menu) the port became available. I don’ use the server yet, configured the printer to be connected directly to the serial communication of Repetier. Hope this helps…