My computer is a Toshiba Satellite P505-S9845. It came with Windows Vista Home Premium x64 and was just upgraded to Windows 7 Home Premium x64 via the Toshiba free upgrade program.
The printer in question was installed and ran properly under Vista.
Today, I downloaded Windows 7 driver for the printer from Lexmark's website. I ran the installation routine and plugged the printer into its old port at the prompt. It recognized the printer and the installation continued.
The trouble started when I tried to print a picture in IrfanView. I clicked to print. The print dialog popped up, showing the Lexmark as the default printer. When I clicked on print, it said there was a problem communicating with the printer and that I needed to enable bidirectional communication in the printer properties.
I went to Control Panel>View Devices and Printers>clicked on the Lexmark Z1300>Customize>Ports and clicked on the check box beside Enable Bidirectional Communication. After exiting Control Panel, I tried to print again, only to be greeted by the error message.
Rebooting and even plugging the printer into another USB port have not changed anything.