Hi coverland
Was it “PAGE_FAULT_IN_NONPAGED_AREA”?
Which avast! version? Is it 6.0.1000 or a pre-release?
Most installs for me have been trouble-free but I have seen something like this on a couple where it annoyingly took more than one reboot before rock-sold stability returned.
At the time this http://www.microsoft.com/downloads/en/details.aspx?FamilyID=ec4b7d80-79b6-4035-92a3-3992a9e09718&displaylang=en was suggested by avast! team as a possible cure but I haven’t needed to actually try it.