Comment spam is a fact of life if you have a blog. Using WordPress, you have not only solid built-in tools to prevent comment spam, there are also a wide range of comment spam protection and defense plugins and methods to choose from if you feel you need additional coverage and protection.

There is no “one size fits all” method that will protect your comments; spammers use many tactics. Consider using multiple defenses. Remember spammers change the way they attack so you must keep your choices updated.

Here I’m listing some plugins which you can use to protect / block spam comments / spam
trackbacks / spam
pingbacks -

1. Akismet – Akismet checks your comments against the Akismet web service to see if they look like spam or not and lets you review the spam it catches under your blog’s “Comments” admin screen.

2. WP-reCAPTCHA – reCAPTCHA is an anti-spam method originating from Carnegie Mellon University which uses CAPTCHAs in a genius way. Instead of randomly generating useless characters which users grow tired of continuosly typing in, risking the possibility that spammers will eventually write sophisticated spam bots which use OCR libraries to read the characters, reCAPTCHA uses a different approach.

reCAPTCHA has earned a very prestigious reputation among the various CAPTCHA systems available and is used by such sites as Facebook, Twitter, StumbleUpon, and a few U.S. Government Websites such as the TV Converter Box Coupon Program Website.

3. WP-SpamFree Anti-Spam – An extremely powerful WordPress anti-spam plugin that eliminates blog comment spam, including trackback and pingback spam. Finally, you can enjoy a spam-free WordPress blog! Includes spam-free contact form feature as well.

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1. WordPress Exploit Scanner – This plugin searches the files and database of your website for signs of suspicious activity. It will not stop someone hacking into your site, but it may help you find any uploaded or compromised files left by the hacker. It also examines your list of active plugins for unusual filenames.

2. WP Security Scan – This plugin scans your WordPress installation for security vulnerabilities and suggests corrective actions. It suggests user passwords, check file permissions, scans database security, hide wordpress version, scans wordpress admin protection/security, removes WP Generator META tag from core code.

3. Antivirus for Wordpress – This plugin monitors malicious injections and warns you of any possible attacks. With multilingual support. Simply, the plugin you must have.