If your connection isn't too slow, you might try another download, if you
haven't already.
Otherwise, I'd consider that this may be a software conflict of some
kind--probably using MSCONFIG (start, run, msconfig) and hitting the
diagnostic startup button, but then checking off Windows Installer on the
services tab, and restarting, might be the way to go--this should eliminate
most third-party startup items.
If that turns out to be too restrictive--i.e. the install errors out--you
could use the button on the services tab (hide all Microsoft services) to
disable just third-party services. This isn't very accurate, though. I see
9 items on that list on my machine, and at least 5 of those are Microsoft
services--but probably beta.
At any rate--using MSCONFIG to eliminate other running startup items that
might be interfering is what I can think of.
I suppose this could be a video issue of some sort, too--and you might look
into whether your video vendor has a newer driver for your equipment.
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