The message “Warning visiting this site may harm your computer” can either come from your antivirus app. or from your browser (Chrome, Firefox, …).. However it’s very simple to tell if it is from your browser being high jacked by a virus. First, any advertisement about some product you should buy is a way to know you should not trust the program. For exact examples or to learn how to solve this check out this Warning: visiting this site may harm your computer!
If you do some online Google search and notice some advertisement under the search box asking you to buy some protection program: this is but a scam. Another example would be a good website you do happen to visit on a daily basis. So you know are on a good website and your browser is telling you the reverse: start thinking your computer is rather infected. To delete this kind of viruses is not always easy. That is why we recommend the pro’s over at this Remote PC Repair site. Another place to go to learn more about similar threats is this Malware Removal site.
Normally when people keep getting this type of message on just about every site they visit it’s very easy to know your infected with something. First, reset your browser and double-check if your problem is solved, or not. It will eventually clean the threat, but not for everyone. To scan your computer with the right antivirus application is the next logical step.
If this method does not resolve your issue then you most likely have a deeper infection and more than one threat installed on your computer. The best thing you can do is to learn more about the fake security software they are trying to pitch you. Write the name of the program down and then do a search on one of the above sites about this threat. You will find some guides about how to delete the program found on your system.