Contact Coldform is a secure, lightweight and flexible contact form with plenty of options and squeaky clean markup.
BotDetect Captcha plugin is a powerful captcha protection for WordPress login, lost password, registration, and comment forms.
This plugin adds a new form of captcha to your Buddy Press registration and comment forms.
Use this plugin to prevent bots from spamming your website
NURCaptcha inserts a reCAPTCHA on the Register Form of your site to protect it against spambots.
This plugin provides the *reCAPTCHA* tag for the Contact Form 7 Plugin. It allows the usage of a reCAPTCHA field provided by a 3rd party reCAPTCHA Plu
Protect your site with a video CAPTCHA solution that provides better security and is easier to read for your visitors.
This plugin is a simple captcha that appears when an unregistered user try to register or to leave a comment.
This plugin utilizes reCAPTCHA (with support for Akismet) to help your blog stay clear of spams.
The most advanced protection against sploggers and spam users registration, is fully WordPress, WordPress MU, BuddyPress and bbPress 2.0 compatible
Provides Visually Appealing Captchas to Enhance and Secure your WordPress pages. Fortified with ANTI-SPAM FILTER Protection and SPAM COUNTER.
Parrotify is a revolutionary anti-bot instrument.
Custom login and registration. 自定义登录注册。
This plugin helps block bogus registrations by allowing a custom registration field and answer.
Stop your WordPress website from being spammed by bots and restrict it only to humans.
BotSmasher stops spam by checking comments and registrations against the BotSmasher API.
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