Your scanner does have Windows 7 32-Bit drivers - are for Vista and Windows 7. However there are no 64-Bit drivers for any Windows OS on the Canon site for your scanner and the MS Windows 7 Compatibility site also states that it is 32-Bit compatible but 64-Bit incompatible.

Since 32-Bit drivers do not work on 64-bit operating systems, you are out-of-luck unless you can find a 3rd party driver. _______________________________________________________________________ Disclaimer: You use my posts & forum articles entirely at your own risk. I don't work for Microsoft. I am an unpaid volunteer.

Ohhhh Scoutfu you're the best!! Even FIVE YEARS after the initial post, your intructions mostly apply very well, at least in its principle and with the help of several posts following yours my good ol'CanoScan Lide 35 was installed and working again. Ten years after initial install on WinXP Home! I managed to have the Toolbox 4.9 working on Windows 7 Pro SP1 64 bit, after the error 'Cannot connect to device or TWAIN source not found' when trying to scan from the Toolbox, by applying the recommendation to add 'c: Windows twain_32 CNQL60 ' (preceded by a semicolon) at the end of the PATH system environment variable. Note: when I downloaded the Toolbox from the links available on the initial post, the 4.5 version installer was offered from a web page in Italian or Spanish (or alike), and the installer too. Compare Delcos 3100 Manual here. So I was happy I could actually make the 4.9 english version working:-) Kudos to all for keeping this thread alive and updated for the various Windows versions (while Canon Support let us down on this so long ago). GG user base!:-).