Canon imageCLASS MF455dw Scanner Problems

The Canon imageCLASS MF455dw can scan, but a scan failure may come from the scanner software, the active USB/network connection, or the printer itself. Use a simple scan test to isolate those layers.

Start with a controlled scan test

1. On Windows use Canon MF Scan Utility; on macOS Canon provides ScanGear MF documentation for this model family.
2. Confirm the MF455dw is reachable over the active USB/Ethernet/Wi-Fi path before changing scan settings.
3. Open MF Scan Utility/ScanGear MF and select the MF455dw, then run a simple glass scan as the test.
4. If network printing works but scanning does not, repair/reinstall the Canon scan component rather than resetting the whole network.

If the scanner is not found

1. Confirm the printer/scanner is powered on without an unresolved device error.
2. For network scanning, keep the computer and printer on the same reachable network; for USB, test a direct cable connection.
3. Make sure the current Canon scan application has this exact model selected.
4. Only reinstall scan software after the connection itself has been proven.

If scanning works from one place but not another

If a computer scan works but the printer’s Scan button/workflow does not, troubleshoot the destination software/service for that workflow. If printing works over the network but scanning does not, the network is at least partly working; focus on scan software, permissions and firewall rather than resetting Wi-Fi immediately.

If image quality is the problem

Clean the scanner glass and test one flat original first. Then adjust the manufacturer’s scan settings such as document/image type and resolution rather than treating an image-quality issue as a connection failure.