If not, go to c:windowstwain_32, and see if you have a folder similar to cnql60 they copy the full path of the folder into clipboard click windows' start button, then search "environment", then. To install the twain driver: verify that the scanner appears in device manager (start - settings - control panel - double-click "system") select "hardware" select "device manager". the scanner is located under "other devices" double-click "canoscan"..... The issue is that although the canon supplied driver for the 64 bit windows 7 os loads the wia driver is required for the scanner to operate. the wia driver that came with the 4200f is 32 bit and will not load..
Solved: i have a mf4570dn, and recently upgraded from windows 8.1 to windows 10. i can no longer scan using the mf toolbox utility. i had mf. It worked before but when i connect usb on windows 7 and open canoscan toolbox (or press the scan button on the scanner which opens the same software) it keeps telling me that its unable to acquire twain source.. What you need to learn to troubleshoot common canoscan toolbox twain error. it is already a natural thing to encounter some issues while utilizing your computer..
