Canon MP640 - "No scanner selected" bug in Snow Leopard

Question

Hi!
I use a Canon MP640 printer/scanner combo unit WITHOUT installing any software from Canon. I like to stick with the built-in functionality of Mac OS X. Which means scanning via Preview.app or ImageCapture.app.
Until recently everything worked flawlessly. Have not used the scanner in a while though and now with 10.6.4 installed I found out, that the scanner does not appear anymore in the Preview.app menu FILE > IMPORT FROM SCANNER > ...
Opening up SystemPreferences.app in order to delete and add the printer again only helped for one scan when the scan was invoked with the printer button. Turning the printer off/on and the link between the computer to the scanner was broken again
In SystemPreferences.app Snow Leopard says "No scanner selected" when I choose the printer and click the SCAN tab in the printer/scanner section.
Anybody found out how to fix this issue without installing all the Canon printing/scanning software? I would like to stick with the built-in Preview.app.
Thanks

Answer 1

Sorry to read that nothing has helped to date.
Checking the operation of my MP980 connected via USB and using Image Capture or Preview to scan, the process 'Canon IJScanner1' is the only process that starts when the scan is initiated from either application. And long after the scanning has completed and the relevant applications have been closed the process remains in the process list.
If I force quit the 'Canon IJScanner1' process I then find that the MP980 is not listed in the 'Import from Scanner' menu within Preview. And with this process still closed, if I go to Print & Fax and click on Open Scanner under the Scan button of the MP980, the Canon MP980 scanner queue will appear but with 'No scanner selected' inside the pane.
So I can recreate what you are seeing. But the question is why is your 'Canon IJScanner1' process stopping. If you check your Console log messages, is there any reference to this process stopping or failing?
Checking my log it showed as follows when I force quit the process.
13/09/10 4:34:00 PM com.apple.launchd.peruser.501 (183) ({0x0-0x577577}.jp.co.canon.ijscanner1.scanner.ica{66850}) Exited: Killed
Also, FYI, trying to start the process again manually is proving difficult. Double-clicking on the 'Canon IJScanner1' icon in /Library/Image Capture/Devices starts the service temporarily but then stops soon after. This is shown in Console as follows;
13/09/10 4:42:51 PM {0x0-0x61d61d}.com.twainds.mp980.scangear140800.canon{67810} /Library/Image Capture/TWAIN Data Sources/Canon MP980 series.ds/Contents/MacOS/Canon MP980 series: /Library/Image Capture/TWAIN Data Sources/Canon MP980 series.ds/Contents/MacOS/Canon MP980 series: cannot execute binary file
13/09/10 4:42:51 PM com.apple.launchd.peruser.501{183} ({0x0-0x61d61d}.com.twainds.mp980.scangear140800.canon{67810}) Exited with exit code: 126
The only solution I could find was to restart the Mac but this made the process re-appear in the process list and consequently I was able to scan from Preview again.
Pahu