Hello saline,
I searched the Support Page and found this article on the issue you are having. If that doesn't help, please call Support: 1-800-821-2797.
I'm trying to install my 6500 on a new system. Works fine on my W11 laptop. Using the same cable, I plug into the USB port of the new PC and run PH6500_2.6.21.0_PCL_x64_English. The system cannot find the device. The PS version installs the printer, but nothing prints when I send a job to it.