Trend Micro Internet Security 2008 is blocking access to the internet, even with the firewall set to the lowest level of security. This means I need to disable the firewall in order to use the internet which is obviously very dangerous. How can I fix this problem? The computer is running Windows Vista Home Premium.

Having never used Trend Micro Internet Security it will be difficult for me to provide exact steps for resolving this problem. However, there is some generic guidance which I can provide that should hopefully assist in resolving the problem. To begin, make sure that the Trend Micro firewall is not conflicting with any other security software running on the computer. In particular, it is possible that if other firewall software is running the two are conflicting causing internet access to be completely blocked on the computer. If you are not running any other third-party security software then you should make sure that the Windows Firewall is disabled on the internet connection. In theory, Trend Micro should disable the Windows Firewall automatically when it has been enabled on the computer but this may not have happened. Go to the “Start” menu > “Control Panel” and open “Security” then click “Windows Firewall”. Click “Turn Windows Firewall on or off”. You should receive a message informing you that you need administrator credentials to make this change. Provide confirmation when this window appears. Finally, click “Off (not recommended)” then click OK. Make sure that your Trend Micro firewall is enabled before turning off the Windows Firewall, otherwise you may leave your computer exposed to external threats from the internet.

If disabling the Windows Firewall does not resolve the problem you should next try a fresh reinstallation of Trend Micro on the computer. There is always a possibility that a file within the installation has become corrupt. Make sure that you uninstall and remove all components of the program, so that you can start from scratch again. This can be ensured by following the instructions available at the following page on the Trend Micro website: esupport.trendmicro.com/4/How-do-I-remove-Trend-Micro-Internet-Security-Pro-and-Trend-Micro-Inte.aspx .

The place to look for a cause of the problem is a DNS issue with the firewall. Many years ago when using other firewall software on my computer I found that the firewall software was blocking DNS requests. In case you are not familiar with DNS this stands for the Domain Name System. DNS allows for the translation of human-friendly familiar domain names (such as google.com) into computer-understandable IP addresses (such as 74.125.67.100). The value of domain names is that instead of having to remember a string of numbers for each website you want to visit, you instead only need to remember a memorable domain name. Essentially, the internet would arguably not have been adopted without something like DNS simply because people would not be able to remember the numerical IP address of every website they wish to visit. However, even though domain names are good for humans they are not terribly good for computers. Instead, computers need to use the numerical IP address. As such, when you visit a website the domain name which you type needs to be translated into an IP address to allow communications to take place between computers on a network.

Getting back to how DNS may be relevant to your scenario, I have previously found that firewalls can (mistakenly) block DNS requests. This should not be happening, but when it does you will find that you cannot use the internet. The internet is still working, but your computer is unable to translate the domain names into IP addresses (as the DNS requests are not getting through your firewall). To test this theory, when the problem occurs and you are unable to use the internet, try accessing some websites using their IP addresses instead. For example, in your web browser go to 74.125.67.100 which is one of the IP addresses for Google. All being well, you should see the Google website appear. If this happens, it seems that the firewall is blocking DNS requests. As such, you should look through the configuration of your firewall to check whether there could be anything that is preventing the DNS requests from getting through.

Should you find that the issue is not DNS related and the problem persists, the only other suggestion which comes to mind is to upgrade to the latest version of Trend Micro Internet Security. Looking on the manufacturer’s website (www.trendmicro.com.au) the latest version of the software is version 2009. Since Vista was still relatively new when Trend Micro Internet Security 2008 was released it is always possible that there is some incompatibility that has been resolved in the latest version of the software. That said, you will need to consider that given your experience with the product whether you wish to stay with this internet security solution or try a different product. Before going either way I suggest that you try contacting Trend Micro customer support to see whether they have a ready resolution for the problem, in case they have encountered this problem before. You can find the contact details for Trend Micro technical support by going to www.trendmicro.com.au then click the “Support” link.