Remote Desktop Connection Win 7

I have a laptop (A) with Win 7 Pro and another laptop (B) in a different location that also runs Win 7 Pro. I am trying to use remote desktop connect via internet. Pc cannot initiate connection, returning error about is remote pc on, is it able to accept remote control etc.
PC B has remote enabled, port forwarded, and firewall configured.
PC A has an anytime upgrade from win 7 home to win 7 pro.

I can connect via internet to PC A with a computer running win xp. I can ping PC A's ip address. What is the problem that PC B can't connect to PC A? Is it possible that there are services not running or maybe registry key that is incorrect?

Thank you for your time and help.

I have a laptop (A) with Win 7 Pro and a desktop (B) with XP. I am trying to use remote desktop connect via internet so that I can use printer that's connected to B. Printer is very old with no updates available. Neither can detect internet connection despite already with connected with internet and is asking for domain name.
Connection was successfully before, however it was before there was tech support for XP.