Symantec Error Blocks AOL Access

A faulty update sent to users of Norton AntiVirus and Norton Internet Security prevented them from signing into America Online for several hours Wednesday. According to Symantec, the problem was traced to a part of the software that prevents attackers from accessing a computer through open ports.

Traffic from AOL was mistakenly marked as malicious, which caused the connections to drop, and blocked them from reconnecting. An update was pushed to users approximately seven hours after the faulty one was released, the company reported.

Symantec is recommending users who are still experiencing problems to look at an advisory for instructions on how to correct the issue. Disabling Norton should allow a user to go online to download the updated definition file.

Those still having problems can call Symantec customer support for free at 1-800-927-3991, the company said.

Wednesday's blunder is the second in the past week among major antivirus companies. A bug in a virus definition file issued last Friday caused McAfee's antivirus software to mistakenly mark several applications, including Microsoft's Excel, as infected with the virus W95/CTX. The files were quarantined, and in some cases deleted.