Promark 2 and GNSS Solutions

Hello all, I am a noob here but not a noob to Survey....ughh
So ny query is this we inherited a few Promark2 GPS units and all the attachments download cables etc... we installed office solutions 2.7 to download via usb to serial adapter....it worked for a while, now it doesnt recognize any reciever i assumed it as a driver issue ...no luck, so i installed GNSS Solutions, and every computer and Port I try i get the Data source not Connected error message, I get it on every port on all 3 of my computers , I even hooked up Directly to my serial port on one Computer but no luck, does anyone have any suggestions to what is happening ...simple answers to your obvious questions, Yes the unit is in the cradle and turned on, yes I updated and rolled back drivers on every computer, Windows XP is my main OS except Windows 7 Business on one, please any suggestions would be appreciated, I get no help from Spectra Precision, or Ashtech, Or Trimble!!

Studio,
   I have not worked with that brand before but I would bet most operate in a similar manner. Our Trimble receivers have had an issue like that before and I had to do a hard reset on them to get them to open the port. I don't know how to do that on those receivers but I would guess you could Google it or call the manufacturer tech support to find out. Be careful though, a hard reset on Trimble receivers wipes out any data files.
   Good luck!