The manual duplex dialog box is not appearing when I try to print two-sided output on the LaserJet 1020 printer connected to another computer in our home network. Both computers are running under 64-bit Windows 7 Home Premium. The manual duplex was working properly for both computers until two days ago. Now it works only for the computer to which it is connected. When I request a two-sided job from the remote computer, only the even page prints. The dialog box instructing us to turn the output over and reinsert it into the feed tray does not appear. The printer just sits there with its red light blinking. The problem occurs with more than one kind of software program. The problem occurs whether or not the computers are in a Homegroup.
When the problem first occurred, the two computers were using different drivers. The computer with the printer was using the original driver that came with the printer, and the remote computer was using the driver that Windows automatically downloaded. I have now made sure that both machines are running the same driver, which is the one that Windows 7 automatically downloads and installs. The problem still occurs. I have run the HP Print and Scan Doctor, which has not solved the problem.
Please help.