Canon Toolbox 4.9 not working with Windows 7(x64) Professional

I received my new computer and went through the process of installing the drivers and software for my Canon MF4270.  I downloaded the software directly from the Canon web site to ensure that I had the current drivers and software.  I can print and fax from my computer but I am unable to access the scan feature from the Canon Toolbox v4.9.  I am able to launch Windows Fax and Scan and utilize the scanner.  Based on the fact that the computer can interface with the scanner, I contacted Canon Tech Support.  After working the issue with them for about 40 minutes, they referred me to Microsoft to find a resolution.  I have attempted to shift the compatability mode for the executable (MTFBOX.EXE) and still cannot get the Toolbox software to access the scanner.  Is there a solution for this or am I simply out of luck?



We need to make sure a certain folder path is in your path environment variable.

Let us determine the correct path to add into the Path environment variable.  Look in C:\Windows\twain_32 and there should one other folder in there.  For example the folder name should be CNQ4803.


This is the path that is needed to be added into the path environment variable.




Now, follow these instructions to get to the dialog to modify the path environment variable.

a. Control Panel > System > and then choose Advanced System Settings in the left hand column.


b. This will bring up the System Properties dialog (it should already be on the Advanced tab).


c. At the bottom of this dialog is an Environment variables button.  Clicking this button will bring up the Environment variables dialog.


d. In the bottom panel, scroll until you find the variable named path.  Select this one and then hit the Edit button to bring up the Edit System variable dialog.


e. In the Variable value text box, scroll all the way to the right and then add in the path C:\Windows\twain_32\CNQ4803 that was determined earlier.  Make sure to separate this value with a preceding semi-colon.  And also be careful not to make any other changes to this value.

Now click on OK and check if it works.


If the issue still persists, I would suggest you to contact Canon support for more information:


Hope this helps.

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Question Info

Last updated March 27, 2021 Views 49,783 Applies to: