Unable To Open Twain Source

I am using home built Win 10 and can't get my Canonscan 8400f to work.

Bob

 

There is no driver support for that scanner above Windows 7.
You can try reinstalling the drivers in COMPATIBILITY mode but I doubt it will work.

 

I went on the internet bought a software "Drive Finder" for $29.95 and it doesn't help and the software guy says that if I pay him $250.00 that he could fix it.
The name of the of the company is "Safecart" I think they a scammers.
There are other companys that say there software can fix it but now I can't trust them.

Bob

 

You could have used one of several excellent FREE driver updater programs hosted here on MG, none of which would probably have found anything. But you could have easily found out on Canon's support website that they have NEVER released any driver software for any Windows OS after Win 7 for that scanner.
I have a Canon scanner that I can ONLY use on an old XP system I have as it will not work on Win 8 or 10.
From experience and from reading very widely I believe those people were lying to you.
Before buying that driver program you should have asked here first, but at least you wont do that again in a hurry.

 

This scanner worked on Win7 OK but I just found a software called that is supose to do the job called "VueScan" has anybody here used it?

Bob

 

Canon has driver support for that model for Win 7. Have you tried to run it on Win 10 in Win 7 compatibility mode?
https://support.microsoft.com/en-gb/help/15078/windows-make-older-programs-compatible

 

Why don't you try VueScan?
http://www.majorgeeks.com/files/details/vuescan.html

Your scanner is supported.
https://www.hamrick.com/vuescan/canon_8400f.html#technical-information

https://en.wikipedia.org/wiki/VueScan#Overview

 

I am having trouble downloading VueScan and paying with a credit card.

Bob

 

I get "Unable to select TWAIN source" on the trial software.

Bob

 

I just downloaded VueScan from MajorGeeks.
You don't pay for anything.

Where are you getting this message?

Here's the sample scan I just did.

 

CH]

 

It's impossible to see anything in your screenshot.

Edit: Ok. Click the Yes button and post any info you get.

 

I found this.
https://www.pentaxforums.com/forums...rinting/301653-windows-10-canoscan-8400f.html

You'll need:

CanoScan Toolbox Ver. 4.9.3.2.
http://support-ph.canon-asia.com/contents/PH/EN/0900293303.html

Windows 7 driver ver. 10.2.3.1a.
https://www.canonprintersdrivers.com/canon-canoscan-8000f/

Disclaimer: I cannot vouch for this info. Set a System Restore point!

 

Well I finally got "VueScan" to work, thanks to my grandson in Iowa and boy is it fast.

Thanks to all of you that tried to help.

Bob

 

Great.
Any idea what the initial issue with VueScan was?