Jeff,
This is interesting! I’m also using XP on an IBM ThinkCentre, with a recently-acquired Canoscan 8400F; I doubt the software architecture will be very different. And yet mine has only ever offered one data source (the true TWAIN one, without the WIA prefix).
The strange thing is, I have been experimenting with disabling WIA recently, for reasons that you can read about in my recent thread on this forum: “Weird interaction between TWAIN and WIA DSs for same scanner”. Now that ought not to affect the Canon at all, since it doesn’t offer a WIA data source – but it does – in a variety of ways that I haven’t documented systematically, not least because for the most part they are not reproducible. Suffice to say that I have come to the conclusion that for the Canon to work properly, the WIA service needs to be enabled – even though it doesn’t offer a WIA data source.
It sounds like an appeal to Canon Tech support is in order. They have been no help at all so far, but they ought to be able to say whether the Canoscan 8400F and 8600F are supposed to offer both TWAIN and WIA data sources, or just the former. In fact, I’ll do it right now.
I would have copied it to you, but no email address in your profile, so instead I have appended a copy of the email I sent to canon_support@techteam.com.
Andy
Dear Canon tech support,
Please see the following link:
http://www.twainforum.org/phpBB2/viewtopic.php?t=1545
relating to WIA-related problems with Canoscan scanners under Windows XP.
I recently acquired a Canoscan 8600F. In my experience, most scanners under Windows XP will offer two data sources: a TWAIN one and a WIA one (same name, with WIA- prefixed). My Canon only offers me the TWAIN one – but I have found that nonetheless, it only works properly if I have the WIA service enabled. It shouldn’t make any difference!
Jeff, on the other hand, has a Canonscan 8400F, which originally offered both data sources, but recently developed problems associated with the WIA data source.
My question is: are these scanners supposed to offer both data sources, or only one? They are such similar models I imagine both should behave the same in that respect. In other words: it seems like either Jeff or I ended up with a bad installation originally, but who is it?