Other Ways to Avoid Spam

An advanced method to stop e-mail harvesting bots is to have a link to a dynamic perl/PHP/ASP page. The purpose of this script page is to check who is looking at it, and ban them from your website. In order for this to work, you must have a link to the dynamic page hidden somewhere on your site. It must be hidden somewhere in the HTML code, so that only a bot would find it. When the bot sees the link, they will try and follow it. The code in the scripted page would then ban that user from visiting your site again.

Since we don't want to ban good bots, an entry would need to be made in robots.txt telling them to stay away from the dynamic script file. That way, bots who obey the robots.txt file will be safe, and bots who don't will get banned.

It's important to note that this is a far-from-perfect method. Banning would typically be done by IP address. Since many bots use dynamic IP addresses (which means they change frequently), a bot might later be able to access your site. Even worse - someone who gets stuck with a bots old IP might never be able to access your website!

Instead of using the usual code shown above to display your e-mail address, it is possible to use javascript to make the code look different. The e-mail address will still look exactly the same to the end user, but the actual code will look different. This helps hide the code from bots, who usually only look for the specific e-mail syntax.

Some websites replace e-mail addresses with pictures that look like text. So, instead of being able to click on an e-mail address on the website, the user will have to manually type it in to their e-mail program. The confusion of not being able to click on the e-mail address might frustrate some users. However, the worst part is that these images aren't safe from newer e-mail harvester bots. For more information, be sure to look at The Harvester Bot of the Future.