DIAGNOSIS The scanner driver on your computer is either missing, corrupted, or being blocked by your security/firewall software. It’s a software handshake problem, not usually a hardware one.
FIX First, ensure you’ve installed the full software package from the Canon website, not just the basic drivers Windows auto-installs. 1) Download the “TS3500 series Full Driver & Software Package” from Canon’s support site. 2) Uninstall any existing Canon printer software from your computer’s control panel. 3) Run the new installer as an administrator (right-click, ‘Run as administrator’). Make sure to connect via USB during installation if prompted, even if you plan to use wireless later.
IF THAT DIDN'T WORK If the software is installed, the communication can be blocked. Temporarily disable your Windows Defender Firewall and any third-party antivirus (like McAfee or Norton) and try the scan again. If it works, you’ll need to add an exception for the Canon software in your security settings.
HEADS UP The IJ Scan Utility that comes with the full package is more reliable for scanning than the generic Windows scanning dialog. Use that dedicated program for best results.