The bug only affects software using an early version of the engine that reads the so-called Dat files. NAI denies responsibility for any inconvenience caused because, it maintains, users should not only ensure they download Dat antivirus update files but should also ensure they keep abreast of the engine updates for reading the Dat files, too.
David Emm, NAI's business development manager for VirusScan, said, "If a Dat file is over six months old, the software will holler at you to update it, but the user is responsible for keeping the engine updated."
Michael Schaefer, IT manager for Chase De Vere Mortgage Management, said the bug hit his company's computers at lunchtime, just after the latest antivirus update was received.
"Five minutes after distributing the Dat files, I started to receive calls that the network was down. The problem was finding the actual cause because, as the updates have never caused problems before, I naturally assumed it might be a problem with the network, the servers, hubs or something like that," he said.
Once he tracked down the cause of the problem, Schaefer said, the resolution was simple, but only because the company uses ghosting (mass distribution) software - for many companies it would mean visiting each machine individually.
The problem is created by the 4.0.02 version of the engine, which Emm explained is two years old and therefore is no longer supported. Schaefer argued that he only bought the software nine months ago and feels that NAI could have made a better job of testing the effects of the software before distributing it.
Graham Titterington, a senior consultant with analyst firm Ovum, said he thinks two years is not very old for software and suggested the product should still be in the support window. He added, "It is an egg-on-the-face situation for Network Associates. In its line of business customers expect impeccable standards. A slip-up like this is, therefore, more serious because the customer relationship is built on trust."
The affair is making NAI look at its whole update strategy. "We were surprised at the number of customers with the older engine," said Emm. "There is an internal discussion going on at present to see how we can flag up the need to upgrade the engine from within the product, rather than making it solely the user's responsibility."
NAI has resumed support for the offending engine for the time being.