Windows 7 - unable to open com port , in use by another program

I am using windows 7 64 bit, I have tried all of the latest drivers and rolled back to older drivers, I am using the Digi port software to create the Virtual Coms , I am using Putty, MettaAssist View, and Hyperterm, cannot get any of these to work, other machines in office using the same setup have no problems connecting.

Please Help.

Which Digi software are you using? RealPort?