Captcha without cookies or sessions
One problem I have had with adding captcha to my blogs is that virtually all of the plugins available require sessions to track the “magic code” via a cookie on the server side. Well this creates a big problem because many visitors turn off cookies by default for sites they are not familiar with which will make the post fail, then they have to hit the back button and because sessions are active, most browers will see it as an expired page so it empties out the comment form! That’s very fustrating and I have experienced myself on many blogs where I gave up commenting entirely because it was too annoying.
Well I finally found a decent WordPress captcha plugin I could modify easily enough. “Anti Spam Image” by Nio can be found over here:
My version uses MySQL instead of sessions to keep the code available for 30 minutes to the visitor. I’ve posted my modification at the bottom of his comments or you can get it here:
(backup download location: http://pastebin.ca/168697)