Sometimes after running a boot time scan overnight, the PC will be found shut down (powered off) in the morning. The power settings are all set to never shut down or go into sleep mode, etcetera. The PC is on a fully functioning UPS, so incoming power is not an issue. The keyword, I suppose, is sometimes. I’ve never seen it happen if boot time scan is run during the day. The PC will simply boot to the log in screen after scan completion, as one would expect. About 50% of boot time scans that are run during the night though, exhibit this “shut down” behaviour, where the PC is found powered off in the morning.
The PC is runining Vista Home Premium SP-1 32-bit, and is kept up to date with all Microsoft updates, patches, hotfixes, etcetera.
PC hardware: 2Gb RAM, Intel Pentium Dual E2180 @ 2 Ghz
Internet connection: DSL w/Checkpoint Firewall (strict settings)
Avast Professional (Build: Feb2009 4.8.1335), auto-update, and manual updates dome from time-to-time.
Concerns:
1.) Although the machine scans clean, perhaps there is a trojan, allowing external access from this machine once it is rebooted to the log in screen?
2.) Is something being found by Avast, but the malware is catching that fact and simply shutig down the box?
Any thoughs?