If you use ZoneAlarm do not install KB951748 as it will kill your internet access.
If you have it installed uninstaling it should cure the problem.
An alternative solution is to lower your internet security slider from high to medium in ZA or uninstall ZA (not recommended).
A solution from ZoneAlarm which should allow you to install the update.
(not tried it myself)
http://forum.zonelabs.org/zonelabs/b...ssage.id=52727
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