When it worked fine on Windows Vista, was that with IE9, or some other
Not that I think anyone here will have a solution. it is not really a C#
or even .NET question.
However, I can confirm that even since the IE8 beta, IE has had trouble
printing things correctly. In the worst cases, the page does not even
print correctly directly from the browser, but in other cases you can
get a good printout but print preview is wrong.
I have not seen the exact problem you are describing, but it would not
surprise me to find that printing via automation uses a different code
path than printing straight from the browser, and that there are bugs in
that code path.
Note that at least in my own experience, the problems were 100%
reproducible. That is, scenarios that did not print or display correctly
never worked correctly, no matter how many times one would try. Your
post is not specific about reproducibility, but if for a given document
it always prints incorrectly, it is probably a similar bug or bugs in IE
to those that I have seen myself.
Anyway, I realize none of that is helpful. I suppose you might try
reinstalling printer drivers, looking for different ones, etc. on the
possibility that it is a driver issue. But other than that, I do not have
much to offer in the way of help. Just commiserating. :)