Funny I just reread this post again over the weekend (don’t remember why) and I then I reread the cap description. From the twain spec under Application for CAP_DEVICEONLINE:
“This capability can be issued at any time to determine the availability of the image source hardware .”
You *should* be able to use this to determine if the hardware is online. The spec makes no mention of having to be between states 4 and 7 – and while the spec is not always 100% accurate (severe understatement) I believe in this case it is correct. I’ll double check this with a couple of drivers that I have installed and update this thread within a day but until then I’m going to stick to my original answer; use CAP_DEVICEONLINE.
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