I think it was Saturday when I was able to view my blog, but every time I click on any WordPress post on this blog, I got a 404 error – page can not be displayed. I was puzzled and didn’t know what would cause this. I certainly didn’t make any changes on WordPress settings and I don’t have at time of writing any non-default plugin. The only change I remember making was on Hotlink settings on cPanel to test stopping other sites using images from one of my sites. Anyway, I’ve disabled the settings as I was just experimenting with the option.

As you might expect, I Googled for “404 on page and post wordpress” and found the following report.

The reporter, Randa, apparently tried to delete the “uncategorized” category, but that wasn’t my case and didn’t answer why every post link I click on the front page is throwing a 404 error. After some digging, I found the solution by using the following easy steps:

- Login to WordPress Admin Panel
- Click on Settings
- Click on Permanlinks
- Hit Save Changes

As you can see, the solution is very easy and could perceive as silly, but it did work for me and that’s what matters. I discovered the above steps when I changed the Permanlinks back to Default, which resolved the issue. When I changed it back to Custom Structure, access to posts and pages still works.

Hopefully, the above will help resolve the same issue someone else is seeing without going through any radical solutions such as reinstalling WordPress.

Now, deleting previous post revisions can be done easily from phpMyAdmin which is available with most web hosting providers from cPanel or other hosting control panel. Once you are on phpMyAdmin, select the database of your WordPress blog, if you have more than one, and run the following SQL statement:

DELETE FROM wp_posts WHERE post_type = “revision”;

The only draw back of removing previous revisions is that you won’t to go back to earlier version of posts. On the plus side, it will help reduce the size of WordPress database and process queries much faster (when blog pages are served to users).

There is also the AutoSave option which automatically save the content of the post at an interval, just in case the WordPress admin page is closed accidentally or Internet connection is lost before you had a chance to save your work.

There are downsides to post revisions, especially if you are the only author of your blog:

MySQL database grows unnecessarily

Let’s say you just started a new blog a few weeks back and you managed to create 20 posts. If those 20 posts got edited or changed 5 times each, you will technically have around 100 posts stored in the database. That’s a lot of posts that you don’t have. This caused the size of WordPress database to grow and use up space unnecessarily.

Slow Database performance

MySQL is a pretty solid and robust database, but bloating it with unnecessary content, such as post revisions, can have a detrimental performance impact on your WordPress blog, especially in the long run. In other words, you may notice a delay when saving new posts, loading your blog or making other changes that involved WordPress database.

In order to turn off and disable Post Revisions in WordPress, add the following line to your wp-config.php:

define (’WP_POST_REVISIONS’, false);

wp-config.php can found on the root directory of your WordPress installation folder. If your WordPress is self-hosted and you are using cPanel Control Panel, go to File Manager, then click WWW folder icon. You should be able to locate the folder of your WordPress and click the right folder icon. With cPanel, you can edit wp-config.php by clicking the file from the list and Edit File from the top right hand side. This saves you downloading (if you don’t have a copy), changing and then uploading wp-config.php.

Once wp-config.php is saved with the line above, WordPress will no longer save post revisions in the MySQL database, except AutoSave ones, which are not saved after you done saving the post.