My old computer quit. Win XP. Had another XP my kids used in good working order (I am posting from it). Hooked up an old HP 750C that I was using on the dead computer, worked fine with it. Now I cannot get the HP 750C to work. I can't find my original software. Downloaded drivers off HP website and used "install new printer" to try to get it up and running. Serial cable (no usb on plotter). It did not come up upon connection (not plug n play???) I have tried everything I can dream of, any suggestions short of buying a new plotter which I may very well have to do.
Get WinLine Drivers. A little pricy, but will get it going if all else won't work. Used it to get my 450C to work with Windows 7. It is hooked up parallel though and not serial. Also, you might try assigning a different plotter to see if it will communicate with the computer.
Well after working hours, installing and unistalling software, downloading drivers off the internet, searching frantically for my original software that I never found, reading countless troubleshooting advice off the internet......I finally figured out that I had hooked the wrong cable (too many cables) to the back of my computer and was printing to nothing. Now it works fine. At least I did get it working. I had almost talked myself in to buying a new plotter. I may anyway.
Been there so I feel your pain. I had a box full of cables and did not know which worked with what. So I bought a box of Avery round key tags and some zip ties and spent an afternoon testing and labeling cables. I determine what each cable worked with, wrote that on a key tag and then zip tied it to the cable. Still have that box of cables but now I know what each one does. Great nerd activity for a rainy day...