1. Install and enable Akismet: The first line of spam defense for your blog is a plugin that comes with WordPress. Akismet also has an API that can be adapted to a variety of Web applications. Once this plugin is in place and active on your site, the majority comment spam will be sent directly to your comment spam folder and will never be displayed to visitors on your site. Akismet alone however won’t stop spam: some spam will get through and spammers will still be able to overload your site with their bots.
Blogger Strategy: You can use Akismet in Blogger/BlogSpot blogs, by installing alternate comment-forms (Disqus or IntenseDebate).
2. Blog comment settings: Change the number of links allowed in comments. Because comment spammers are notorious for their links, be sure that you set your blog to a low number of allowed links in comments. In WordPress, the recommended level is “1,” unless you want to have every comment go into moderation. This technique is effective in reducing the number of spam comments that are displayed on your blog, but it does not prevent access to your site by spammers. Another setting you can use to combat spam is the “Spam words” list. By creating a list of words you consider spam, you redirect all comments with those words to your comment moderation queue. In WordPress, these settings are found in the “Settings,” “Discussion,” “Comment Moderation” section of your dashboard.
In Blogger: The exact spam detection checks employed by Blogger are not known, but it does filter out some comments as SPAM with 2 or 3 active links in them. As of now, there is no publicly available list of 'Spam words' and there's no option to create one yourself for your blog. You can recommend these features to Blogger over here:
Blogger Help Forum.
3. reCAPTCHA: This plugin works like the CAPTCHA images you type in all across the Internet. These things are annoying to many users because of the difficulty associated with figuring out what each image is. Still, requiring random human input before accepting a comment will stop automated spammers in their tracks.
In Blogger: You can activate CAPTCHA (word verification) at
Blogger Dashboard -> Settings -> Comments.
4. Stop comments without referrers: If you are experienced at Web programming, you can modify your .htaccess file to block comments that are received from users with no referrers. There are several ways to do this and you can disable your blog if you do something wrong, so be sure to back up your original .htaccess file and only follow directions from a reputable source. You can also use a custom WordPress function to make this happen. Search the WordPress site and Google to find out all your options.
In
Blogger, adding or editing htaccess files is not possible, so this is limited to WP users.
5. Close comments on old posts: In your WordPress dashboard you can go to the “Discussion” section of your “Settings” area and define the age at which posts close to comments. This reduces the amount of spam that comes to your blog and also helps keep your online community fresh.
In Blogger, you cannot completely close comments for older posts (you CAN do it manually by editing each and every post), but you can activate and limit comment moderation only for your older posts. Go to
Dashboard -> Settings -> Comments and against
Comment moderation select the number of days.
6. Wp-Ban will do a lot for you in the fight against spam: Rather than just routing spam comments to your spam folder, Wp-Ban actually prevents spammers from gaining access to your site. Every comment in WordPress is stamped with the user’s IP address, so all you have to do is populate a list with the adresses or domains of all your site’s spammers. This makes a huge difference in the volume of spam you get delivered to your blog: just remember however, it is not foolproof.
Again, for
Blogger/BlogSpot blogs, this can be done only via Disqus or IntenseDebate.
7. Change the name of your comment file: In WordPress, almost everyone’s comment entry file is called “wp-comments-post.php.” Rename the file something different such as “wpcom.php” and then go into your WordPress dashboard to edit your theme to include the
new name. Because the one file spammers look for isn’t there, they will not be able to leave spam.
Blog spam is a nuisance that rarely goes away by itself. In fact, the longer your blog is operational, the more spammers will attack your site. Use these 7 ways to reduce blog spam and get some relief. Be sure to try more than one of these methods to maximize the amount of spam you block.
If you are working on Blogger/BlogSpot platform and comments-SPAM is a serious problem on your blog, then I would advise you to switch to either of the freely available alternate comment-forms (Disqus or IntenseDebate). You can read more about their SPAM-fighting strategies here:
Disqus &
IntenseDebate.
