OK, so I recently encountered some problems with Avira Anti Vir: the VDs just wouldn't update! However, I specifically reinstalled my entire security apparata afterward to make sure it recognized the new setup. It isn't the firewall; there are no block alerts, no popups asking me to block or allow the AV to download. It can only be updated manually by downloading its definition files. If that doesn't help I would look into two things, an infection or a problem with your firewall.
The Federal Bureau of Investigation and the Inglewood Police Department are asking for the public's assistance in identifying the individual(s) responsible for the homicide of Kevin Robert Harris II in Inglewood, California.