General scanner troubleshooting

Updated: 01/24/2018 by Computer Hope

Verify cables connected properly to the back of the scanner

If the scanner is a parallel port scanner, it is likely it has two available connections on the back of the scanner. Verify the cable coming from the computer is connected to the IN, Computer IN, computer, or similar connection.

Ensure that the scanner is getting power

Computer scanner

If your scanner is not getting power, we recommend you check all the scanner's electrical connections. Make sure they are connected properly at the back of the computer, at the scanner, and at your wall outlet. If the scanner's power cable is plugged in to a power strip or surge protector, temporarily connect the scanner directly to the wall, to verify the power strip is not causing the problem.

If the computer scanner is getting power, you should notice the inside light come on when the power is first received by the scanner.

After checking the connections, if you still get no power to the scanner, it is recommended you contact the manufacturer of the scanner.

Parallel port scanner troubleshooting

If you have another device connected in between the scanner and the computer, turn off the computer and temporally disconnect the devices connected to or from the scanner. If, after disconnecting these devices, the scanner works, it is likely that another device may have issues or may be unable to work with other parallel devices.

PC Windows users verify no TSRs are running in the background

Press Ctrl+Alt+Del and end task all currently running software, except explorer and Systray, and then scan again. If this resolves your issue, it's possible that an application in the background, such as an antivirus program, is preventing your scanner from working properly.

Verify the LPT port mode

PC users should ensure the LPT port mode in the computer BIOS is set to either EPP or bi-directional mode, or try alternating between these two modes.

Update the drivers

Verify the latest drivers are installed for the operating system being used on your computer. For a listing of computer scanner manufacturers and links to driver downloads, see our scanner drivers page.

Additional information