A faulty firewall anti-virus update left thousands of Barracuda Networks' customers without e-mail earlier this week.
Over three-quarters of the supplier’s 35,000 customers were affected by the problem, which lasted for two hours on Tuesday.
Their systems had downloaded an incomplete anti-virus update file, which caused their Barracuda appliances to stop all e-mail traffic and store it in a queue. Barracuda sent out a fixed file to rectify the problem.
The process of storing e-mail in a queue instead of distributing it, when a problem occurs with updates, is a default action in the supplier’s anti-spam solutions. Barracuda specialises in providing anti-spam appliances to businesses.