Cisco 2600 console connection

New to CCNA, trying to get my 2600 router to bootup all parameters set correctly and console cable terminated to only serial COM1 port on my PC. When I open a session and try to connect,error message is cannot connect to COM1 port, port is already in use!
However, I know this not to be true, I’ve checked device manager for any conflicts and nothing, only have USB ports as other ports….??
Please help if possible