Unable to open twain source its been working well on my new dell xps8700 running windows 10 for over 6 months. suddenly i get "unable to open twain source please check connection then re-start toolbox" unplugging and plugging the connection the computer gives the little beeps acknowledging the connection.. Canon scanner – unable to open twain source. unable to open twain source please check connection then re-start toolbox. finally, i restart the canonscan toolbox. now my scanner works without any issues and the same should be true with your scanner. newer post. older post.. Canonscan twain source not found annavi apr 29, 2014, 6:48 am i am on windows 7 and i am trying to use an older canoscan n67ou scanner .i have downloaded the toolbox 4.9 version and the.
I have a canon canoscan 4400f scanner and the other day i was unable to get it to work. i use the canon software canoscan toolbox to operate the scanner and when trying to scan i was getting …. Hi allhaven't used my scanner for a while.when i try to scan it displays a message box titled canoscan toolbox with a big exclamation mark that says "unable to select twain source"in my comp the.... 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..
