"Unable to open TWAIN server" Please assist

This is an issue with the Driver Installation, Get the drivers Uninstall and reinstalled from the CD.

Driver mismatch - the driver of the scanner has forgotten the location of the TWAIN driver because another software has been using it lately. Follow this
http://weblogs.asp.net/jeffwids/archive/2009/11/02/canon-scanner-unable-to-open-twain-source.aspx

Maybe their servers are down temporarily...
Seems to be working at the moment...
Have you tried here.?

I hope this information allows you to resolve this issue. If you need further assistance, please post back with a comment to this thread.
If I've managed to answer your question or solve a problem, please take just a moment to rate this post....thanks!

Dear DDuck,
there is no Vista driver for this scanner, thatswhy it is not working with Windows Vista.

Regards

tried uninstallin and installin canon scanner drivers..nothing works..still seeing unable to select twian source..

so i tried an alternative..here we go..
on vista 64 os/vista any version..click Start>All programs>Windows fax and scan

next click new scan on top and that got me going.

some say there are issues with the way usb talks to old scanners with new operating systems like mine (vista 64). hope it helps until you find the actual cure.

For any device to work you need 'drivers'. It is difficult to find a driver for an old product with a new OS like vista. You can try to get drivers for XP or Win2000 and use them.

S. Mohan

Could be a problem with the cables themselves. Try a new set or different set of cables and see if this resolves the issue. Also make sure that you installed the correct version of the driver for your OS.
Should you still have difficulties, try a clean boot as explained below:
http://www.fixya.com/support/r545614-installation_problems_clean_boot_install

(Just replace "camera" in the procedure for scanner.)

see this site from where you can find help.
Sergio
http://www.bitvise.com/how-the-net-works

Mine was doing the same thing. When I get on the program, before I click "acquire" to preview and scan, I click OFF the toolbox and then everything seems to be okay and I can go ahead and scan.

The download website for your scanner is here:

http://www.usa.canon.com/consumer/controller?act=ModelInfoAct&tabact=DownloadDetailTabAct&fcategoryid=351&modelid=8008

A TWAIN driver is simply a generic scanner software driver that your specific Canon software can hook into and use.

I recommend starting with this one and see if it installs the TWAIN driver you need:

"CanoScan Toolbox v2.2.3 for Windows 98/Me/2000/XP"