I don't know if this is going to help you, but I had a similar message which
took me to KB834938 - also a "DRIVER_IRQL_NOT_LESS_OR_EQUAL" message and I
was similarly appalled by the fee demanded for a hotfix.

However, I noted the file concerned and especially the version number
(minimum) listed in the KB article.   I then searched my computer for the
file concerned and found 2 copies.    One with a version number below that
stated by Microsoft and the other with a version number higher.   So I
copied the higher version number to the file with the lower version number
and overwrote it.       That was a few days ago and, not intending to tempt
Fate, so far so good.

So you might want to check the version numbers of the 5 files listed in your
KB article and see how they relate to the versions listed and if any are
lower version numbers try and get a higher version from somewhere - either
search your own computer or try a Google search for the files.     Do make a
copy of the files and their locations before over-writing just in case this
doesn't work and you have to go back to where you started.

I'm not speaking with any authority on this except that it seems to have
worked for me.

Good luck

Martin