Where do I find a twain driver for the scanner?

I haveCanoScan LiDE25 and Win8.1

Install the device driver first:

                Run "lide25vst6411011aen.exe" by double-clicking it OR

                Open the folder "lide25vst6411011aen" then double-click "SetupSG.exe"

Install the CanonScan Toolbox:

                Run "cstbwin4932en.exe" by double-clicking it.

Then in "This PC"->System Properties->Advanset system settings->Environment Variables->

System variables->Path  Edit this line by add ";C:\Windows\twain_32\CNQL25" end of line.

Check is the you path right.

Follow the instructions and reboot the computer to complete installation.

perhaps if you run all exe by in Admistrator mode it would edit this path ?

Thaks for http://www.youtube.com/watch?v=rYQKh8WkAKE

Process is largely correct, but to get our 5200f working on Windows 8, there's a few differences:

(1) 5200f drivers will not be "found", so you must manually install these.

(2) The most up-to-date- CanoScan Toolbox software will not work and will continually fail with the message "unable to select TWAIN source".

So this is the process I used:

Install the device driver first:

                Run "5200fvst6410160a_64en.exe" by double-clicking it OR

                Open the folder "5200fvst6410160a_64en" then double-click "SetupSG.exe"

Install the CanonScan Toolbox:

                Run "cstbwin4932en.exe" by double-clicking it.

                Follow the instructions and reboot the computer to complete installation.

When the CanoScan 5200f is connected and switched-on, it will complete calibration actions when

the computer reboots. This is a sign that the device driver has recognised the scanner.

Latest CanoScan Toolbox software V5.012 installs correctly but fails to bind to the older device

driver. This is why the previous software version is installed instead.

Fixed mine. There are no Windows 8 drivers available on Canon's website or Windows Update. Follow these steps to install a Canoscan 8400F scanner under Windows 8 x64 in desktop mode:

(1) Download and install the Windows 7 x64 drivers from the Canon website.

(2) Launch Device Manager, right-click and uninstall any (?) unknown device, then rescan for new hardware and the Windows 7 x64 drivers will automatically install.

(3) Download and install the Canoscan Toolbox software from the Canon website.

(4) Launch the Canoscan Toolbox software, select Settings, and click the Reset button to repair the non-working Copy/Scan/PDF/Email scanner buttons.

(5) Reboot.

Button functionality is restored after the reboot. Everything works as designed now. Good luck!

Azskygod: you are a Saint.  Thanks for your excellent advice!

I am running Windows 8.1 Pro and initially had the same problems with my CanoScan 5200F scanner. As per the contributor at the start of this discussion I downloaded and installed the 64 bit ScanGear driver. The system installed it OK but nothing seemed to see it using Twain. It was there in my devices and showed as working correctly but not with any twain compliant program. Previous versions of WIndows worked perfectly with PaintShop Pro as my image editor which was used to scan and edit using the twain driver. So I downloaded and installed the 64 bit CanoScan Toolbox, restarted the computer and then clicked on reset in the Canoscan Toolbox and voila, working. I set Paintshop Pro as my image editor in the Canoscan Toolbox options and all is usable now. Still can't use Paintshop Pro to initialise the scanning as it doesn't show up in the preferences dialog box but hey the CanoSacn toolbox does the job just fine.