1 - Verify that your scanner is ON before launching KronoScan software. Some scanner hide themselves to Windows until they are turned ON. Close KronoScan, Turn your Scanner On then restart KronoScan.
2 - The TWAIN 32bits driver of your scannner must be installed. KronoScan uses TWAIN Drivers because the are the most supported by scanners. Most scanner companies have a TWAIN 32bits driver but they may not install it by default. Go to the web site of the manufacturer of your scanner and in their support section search for the TWAIN 32bits driver of your model.
3 - If it still not working you can import photos and existing scans.
Buying Tip: Before buying a new scanner verify that it have a TWAIN 32 bits driver available. Sadly some scanner do not have a TWAIN driver. Look for a fast scanner. New scanners are 10 times faster than old ones.