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Canon scanner "Unable to open TWAIN source" error.

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#1 DrGreyhound


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  • Local time:11:41 PM

Posted 20 January 2010 - 10:59 AM

Hello all.

Firstly, thanks in advance for any help received.

I have been using my CanoScan D1250U2 for a few months with no probelems. Today I installed the latest versions of iTunes/Quicktime, Daemon Tools Lite and K-Lite Codec Pack.
Since installing these updates I'm getting the following error when trying to use the scanner:

"Unable to open TWAIN source
Please check connection
then re-start Toolbox"

I have searched for fixes on Google. I found three possible sollutions.

1. I have tried re-installing the software and drivers

2. I have made sure the Windows Image Acquisition (WIA) service is set to automatic.

3. I have gone to Control Panel>System>Advanced>Environmental Variables, selected PATH and appended ";C:\WINNT\twain_32\xxxxx" or "C:\WINDOWS\twain_32\xxxxx" (where xxxxx is the model of my scanner).

All with no success.

I'm using Vista Home Premium SP2.

Thanks for reading.

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#2 adriancobb


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  • Local time:06:41 AM

Posted 23 March 2015 - 04:26 AM

It's mostly driver issue. You can try to reinstall the driver. Or you can run a quick scanning check as suggested in http://kb.dynamsoft.com/questions/881/%5BTroubleshooting%5D+Unable+to+open+twain+source. .



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