How to uninstall the Scanner Driver:
Disconnect the USB cable between the Mac and your printer machine.
Reboot the Macintosh.
Log on as an "Administrator".
Select MacintoshHD => Library => Image Capture to open the Twain Data Sources folder.
Delete the printer TWAIN.ds.
Then, you need to delete the ICA driver.
Select MacintoshHD => Library => Image Capture to open the Devices folder.
Delete the Scanner.
*You will find this Scanner file only when the bundled printer driver is installed. If you do not find Scanner file, please go to Step 8.
If you are using a color printer/scanner, you need to delete the Color Profiles.
Select MacintoshHD => Library => ColorSync to open the Profiles folder.
Drag the Scanner.icc file into the Trash bin.
*If you see several Scanner.icc files, please delete all of them.
Empty the trash bin.
Reboot the Mac.