A scanner is not a reverse print queue
A Windows printer queue accepts outgoing jobs; a scanner provides incoming image data to a capture application. A multifunction Canon product can expose both functions, but different interfaces and software may manage them. Do not conclude that scanning is set up merely because a Windows test page printed.
First find the exact Canon model and confirm in its official specifications that scanning exists. Canon's support listing may identify a scan utility, scanner component, or combined package; availability and names vary by model. A standalone printer without scanner hardware cannot gain a scan function from software.
Confirm which device the scan application uses
A capture application can retain an old or similarly named scanner entry after the printer connection changes. Check its selected source and whether the exact device appears. An application that opens but shows no source provides different evidence from one that finds the scanner but fails during acquisition.
If there are multiple identical-looking entries, note connection type and model before removing any of them. Try a small page using the workflow described in Canon's manual. Record whether image acquisition starts, whether a preview arrives, and whether only saving the image fails.
Network print success is not scan discovery
A network Canon printer can accept jobs through an existing queue while scanner discovery uses another service or application path. Confirm the computer and device are on the intended local network, then follow Canon's model-specific scanner setup instructions. A shared printer queue on another computer does not imply shared scanner access.
If USB scanning works but network scanning does not, that difference points toward network configuration or discovery, not proof that the sensor is faulty. Avoid disabling all firewall protection as a shortcut; identify the supported application and network conditions documented by Canon.
Match software to the failing operation
Search Canon's official product support by exact model and operating system. Read descriptions to distinguish print software from the scan component and any optional utility. If printing still works, keep its current driver and queue unchanged while checking scanner-specific requirements.
If neither print nor scan works, investigate the common connection first using the general connections guide. If Windows sees the scanner but a particular app does not, test a second compatible capture application to separate app selection from the device interface.
Interpret a successful test narrowly
A captured preview demonstrates acquisition but not necessarily saving, OCR, or a document feeder feature. Those may involve application settings or hardware capabilities documented for the model. Compare a flatbed test with a feeder test only when the exact product manual confirms a feeder exists.
For malformed printed pages, consult rendering rather than scanner software; for pending print jobs, inspect queues. Windows compatibility and Canon's model-specific support record both matter when choosing software, but neither permits assuming every Canon multifunction model has the same scan workflow or hardware options.