twacker, is you’re not familliar with it, is a sample or model for programmers learning to write applications that use twain. It may not be a perfect app, but I havent (in the last 2 year of writing twain apps) seen it fail as you describe.
If his device doesn’t seem work in a another app (in Vista) and it doesn’t work with twacker I would say its safe to say that device just isn’t working and I would guess at the driver.
Which version of Vista? the 32 or 64 bit?
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