I rather doubt this would be from a virus definitions and engine update, possibly a corrupt installation.

If you have updated to avast6 from the last version of avast5 I would suggest that you try a clean reinstall (assumes you are using avast Pro) on one of these systems:

  • Download the latest version of avast, 6.0.1203 http://files.avast.com/iavs5x/setup_av_pro.exe and save it to your HDD, somewhere you can find it again (if you didn’t save your last download). Use that when you reinstall.

  • Download the avast! Uninstall Utility, aswClear.exe find it here and save it to your HDD (it has uninstall tools for both 5.x and 6.0.x).

    1. Now uninstall avast! (using add remove programs, if you can’t do that start from the next step), reboot.- 2. run the avast! Uninstall Utility from safe mode, first for 5.x if previously installed and then for 6.0, once complete reboot into normal mode.- 3. install the latest version, reboot.