I AM TRYING TO INSTALL MY CANOSCAN D66OU SCANNER ONTO MY LAPTOP ON WHICH I AM RUNNING WINDOWS 7. It keeps telling me that a TWAIN driver is missing and I don't know where to get it from or how to download it onto my laptop. Can you please advise how I can do this so I can install my scanner. Thank you - I appreciate your assistance.

SOURCE: Canoscan 4400F & Vista

It looks like the computers have a hard time communicating with the scanner it will be advisable to download all the current firmware available, her is the link:
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=SupportDetailTabAct&fcategoryid=235&modelid=13810#DownloadDetailAct
This should take care of the problems.

SOURCE: Canon Scanner - Twain Pilot

You can find all drivers, software, and manuals HERE.

I would uninstall what's on the PC for the scanner first, reboot. then start again. Leave the USB cable unplugged untill the software is installed.

Hope that fixes Ya...

Geno

SOURCE: I need a TWAIN driver for a Canon CanoScan N670U

go to http://modrv.com/scanners/canon/402prog.html

SOURCE: TWAIN ERROR AND CANOSCAN LIDE 20 SCANNER PROBLEMS

I had the same problem more than 1 year ago and then found the solution (at least in my case that is) somewhere on the internet. Since I have the same problem with a new computer I searched the internet once more, but did not find the solution. However, last time I was so clever to write down the solution on the disk of my old laptop. The laptop is gone, but not the disk, so I could access it by putting it in an USB enclosure and was able to find the solution once again. Here it is:

c:WINDOWS wain_32CNQLxx (xx is the number of your scanner) should be included in the PATH environmental variable.

Now I know where to look for I found the link where I found it first:

http://www.everythingusb.com/forums/showthread.php?threadid=7337

The entry was by pallosp.

SOURCE: TWAIN ERROR AND CANOSCAN LIDE 20 SCANNER PROBLEMS

Select your operating system and download the driver "TWAIN Driver - LiDE 20 Scanner Driver Ver. 7.0.3.1a_xp" and then download the software "Canoscan toolbox" ...here is the link:
http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=351&modelid=6624