I’m a chinese.My English Very poor.
In china ,some antivirus software can run before the system logon.like Rising,Kingsoft,KV and so on.
In Russia,The “Kaspersky Internet Security 2006” also can run before the system logon.
I use Avast Pro 4.6.623,It looks like can not be run before the system logon.maybe the 4.6.652 version can use. I didn’t try it.
I hope the Avast can be run before the system logon.It means the security can upgrade.
If you understand what am I say,I will very glad.
avast home/pro has a feature called as boot -time scan which scan files before system logon. but this boot time scan available only in NT based systems. to schedule a boot -time scan click menu---->schedule boot-time scan and select appropriate action and click schedule . avast will scan specified location on next reboot
Thank U anbu 8)
Jocksun, the scanning before the logon is ‘boot time scanning’ and it’s present in all versions of avast.
You can update and it will still be there 
Boot time scanning won’t increase the security itself, it will be useful if you need to clean or scan your computer and some files are in use in normal scanning. At boot time, no programs are lauched, so no files are in use and avast! could do its job at that time.
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