Your AntiVirus Update schedule file (\MDaemon\App\AVUpdate.dat) was
renamed to AVSchedule.dat.old by the MDaemon 8 installation so that a
new set of default updates times could be put into place. The new
defaults randomize the times that updates take place but schedule only a
single update per day.
This change should make for faster updates for everyone using MDaemon AntiVirus and SecurityPlus.
If you do not want to have your AV update schedule changed just rename your .old file back to .dat and restart MDaemon.
Additional Comments
This change does not effect any Urgent Update subscriptions you may have in place.