This plugin protects your WPMU signup process against spambots with a simple math question. This plugin is based on the Block-Spam-By-Math plugin created by Alexander Grau. This only protects the new blog creation process and the new user creation process. If you wish to have individual blog protection use the regular Block-Spam-By-Math plugin on individual blogs.
Block-Spam-By-Math
This plugin protects registration, login and comment forms from spambots by adding a simple math question to it ("what is 4+3 ?"). This approach should give you 100% anti-spam protection to your sites....
Safe Signup Form
To stop automated attacks, Safe Signup Form leverages Elliot Back's WP Hashcash -- an elegant anti-spam engine that uses javascript to determine if the form is submitted by a robot or a web browser.
An administration page provides three options for handling submissions identified as spam:
Delete .........
WP-Hashcash
No More Spam
WP Hashcash is an antispam plugin that eradicates comment spam on WordPress blogs. It works because your visitors must use obfuscated javascript to submit a proof-of-work that indicates they opened your website in a web browser, not a robot. If the javascript check fails, WP Hashcash n.........
WP-Hashcash Extended
No More Spam
WP Hashcash is an antispam plugin that eradicates comment spam on WordPress blogs. It works because your visitors must use obfuscated javascript to submit a proof-of-work that indicates they opened your website in a web browser, not a robot. If the javascript check fails, WP Hashcash n.........
Engage & Fight spam
Makes visitors Read More posts and fights spam. Displays extracts from blog articles or simple useful messages and engage visitors to READ MORE while securing your web forms.
No keys/registration needed
Retains users by replacing annoying Captchas and easy to pass client side verification with a e.........
Captcha Bank - Solid Security & Advanced Protection
Captcha Bank = Tough on Bots, Easy on Humans
WP Captcha Bank - Best Captcha Plugin is a powerful WordPress shield which allows you to protect your WordPress website from SPAM. You can display Captcha on Login Form, Registration Form, Comment Form, Admin Comment form, Contact Bank Form and Hide Capt.........
WangGuard
Our API works over SSL, so all connections are secure connections. This is mandatory for all European websites because you are sending information. We are Europeans, so we respect the law, even the most demanding of all Europe, the Spanish law. Use a service that does not comply with all European la.........
SiteBrains Interactive Spam Blocker
Block spam using state of the art client-side form validation. SiteBrains plug-in displays themed notifications to your users as they type.
Our analysis is signed using a secret key unique to your domain.
The signed analysis is submitted in a hidden field along with the rest of the form fields.
This.........
Google Captcha (reCAPTCHA) by BestWebSoft
Google Captcha (reCAPTCHA) plugin allows you to implement a super security Captcha into web forms. Google Captcha (reCAPTCHA) is a free CAPTCHA service that helps to digitize books, newspapers older radio shows.
This plugin can be used for login, registration, password recovery, comments forms.
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Ads Manager WP/BB
Use this plugin to quickly and easily insert Any Ad code Unit to your posts and BuddyPress sections including Forum topics....