Scanning app says no TWAIN or WIA scanner found

TWAIN and WIA are two ways an app talks to a scanner. WIA is built into Windows and used by apps such as Windows Scan, while TWAIN drivers come in the maker's software package and are used by many photo, document and business apps. An app that only supports TWAIN can't see a scanner that has only a WIA driver.

Download the full driver or full software package for your exact model and Windows version from the maker's official support site; the TWAIN driver is usually part of it, sometimes listed separately as a scan driver. Restart the PC after installing.

Many apps have a Select Source or scanner choice in their scan or import menu, separate from the scan command itself. Pick the entry named after your scanner, and if there's both a WIA and a TWAIN version, try the other one.

A 64-bit app can use only 64-bit TWAIN drivers, and a 32-bit app only 32-bit ones. Many older scanner drivers are 32-bit only, so newer 64-bit apps can't list them. Check the maker's site for a 64-bit TWAIN driver, or use a 32-bit version of your app if one is offered.

Press Win + R, type services.msc and press Enter. Find Windows Image Acquisition (WIA), right-click it and choose Restart, or Start if it isn't running.

Install the free Windows Scan app from the Microsoft Store. If it scans, the hardware and WIA driver work and the problem is the TWAIN driver or your app; you can scan here and open the file in your app meanwhile.

If the source is listed but gives an error, uninstall the maker's software in Settings > Apps > Installed apps (Windows 10: Apps & features), remove the device from Printers & scanners, restart, and install the latest package again.

On a Windows PC with an Arm processor, many older scan drivers won't install or run. Use Windows Scan, which works with many scanners without the maker's driver, and check the maker's site for a driver that supports Arm.

For USB, connect the cable straight to the computer rather than a hub, and try another port. Make sure the scanner is switched on, the lid is closed and no error is showing on its screen.

Network scanners often need a small utility, installed with the driver, where you choose the scanner by name or IP address. If the printer's IP address has changed, open that utility and select it again, and consider reserving a fixed address for the printer in your router.

A TWAIN scanner can usually be used by only one program at a time. Close the maker's scan app and any other scanning program before scanning from a different one.