Today’s virus signature update hasn’t just affected me, I see.
After the signature update, Avast flagged and DELETED a necessary file from my Novabackup install: nsMail.dll
And I DID have Avast set to use the Virus Chest/Vault, but the file was deleted. Net result is I had to uninstall and reinstall Novabackup.
That file was definitely not a Trojan, as Avast claimed. Your update needs an update!