I'm pulling out my hair in frustration.
So I have had my RepRap printer (Arduino 2560 controller) for over a year and used it successfully on Repetier Host 1.0. * (something) running on Windows 8.1.
I then walked away for a few months. So, I come back to do some printing and first thing I see is Repetier has an update 1.5.4. So I download and things are good. Until I try to connection...
The standard message that access is denied to COM4. (actually a USB port).
1. I check my device manager, and yes, the computer sees the MEGA 2560 connected to COM 4.
2. i load up the Arduino IDE. Nope it cant talk to any Arduino boards either. Ahh....the ol' Windows 8 unsigned drivers problem!!!
3. I go thru all the steps to re-install the drivers for Arduino.
4. Go back to the Arduino IDE and yes, it can see the boards now.
5. Go back to Repetier. Nope, still can't connect. Maybe I forgot the baud rate setting?
6. I painstakingly try every Baud rate 9600- 128000. Still can't connect.
Any more suggestions?