In the last couple of weeks I have had two PC's (one PIII based system and one Athlon X2) begin to fail to finish shutdown completely. When this occurs they will consistenly go through the 'saving your settings page' then go on to the last blue Windows XP screen just before the machine completely shutsdown then they hang. They have to be shut off by holding the power button. Sometimes on the PIII scandisk will initiate upon the following startup. It does not find any problems with the C:drive. They do this somewhere between 1/3 to 1/2 of all shutdown attempts.
Since they both started about the same time I suspect that it has had something to do with a patch or upgrade that has been installed on both machines but I have no idea which it might be. Antivirus is religiously updated, Zone Alarm runs at the highest security settings. Spywareblaster is religiously updated as well as Spybot search & Destroy. Immunization is updated regularily but tea-time is not run as a resident.
Is anyone else seeing this? Any suggestions on how to fix this?