On Your Side: When ZoneAlarm Apps Conflict

I bought ZoneAlarm Pro to protect my computer. However, after I installed it, I found out it did not have an antivirus program. So I purchased ZoneAlarm Antivirus, but when I installed that program, it deleted ZoneAlarm Pro's protections against spyware, identity thieves, and pop-ups. Zone Labs' customer service department said the applications are incompatible. But shouldn't programs from the same company work together? Nowhere on either program's box does it say that they won't.

Charlie Dickson, Tonawanda, New York

On Your Side responds: When we contacted Zone Labs to determine what causes the incompatibility, the company told us that both ZoneAlarm Pro and ZoneAlarm Antivirus include the company's TripleDefense Firewall. To prevent conflicts, many firewalls will disable themselves when another firewall is installed. However, Zone Labs says that its products do not disable each other, so a user running both should be protected, but that running any two firewalls at the same time is generally a bad idea as it can cause sluggishness and instability on a system.

While Zone Labs doesn't currently warn customers of this problem, it says it is working to find a resolution, including revising the language on its product boxes. In the meantime, it has provided Dickson with a key to upgrade to its ZoneAlarm Internet Security Suite.

Amber Bouman is an editorial assistant for PC World. E-mail her at onyourside@pcworld.com.