Following in the footsteps of our recent popular post “WordPress: To upgrade or not to upgrade, that is the question” we have decided to show an example of how many plugins are not available for the latest (or even the previous) version of wordpress.

When upgrading wordpress, you should always check all of your plugins to see if they will work or have been tested with the version of wordpress you want to use.

Searching for new plugins

When searching for plugins via WordPress.org or from within your wordpress blog (under the plugins, add plugin section) it unfortunately does not let you search for plugins that will work with your wordpress version. The default search result sort order is “relevance”. For the following test we searched for a “popular posts” plugin and have selected the first 10 plugins that met our requirements. Below are all the version stats on each plugin. As you can see, only 4 are stated as being compatible with wordpress version 3.0.2, 6 are stated as only working with previous versions of wordpress. While checking your plugins for the wordpress version may seem obvious, it is something that is overlooked by most users.

It makes it even harder when you are upgrading wordpress and should manually check each plugin for their wordpress compatible version number so that you can be sure you will not upgrade only to find that some, or all of your plugins do not work.

1) WordPress.com Popular Posts
Compatible up to 2.9.2

2) Ranged Popular Posts
Compatible up to 3.0.2

3) Simple Popular Posts
Compatible up to 2.9.2

4) Easy Popular Posts
Compatible up to 3.0.2

5) Yet Another Most Popular Posts
Compatible up to 2.7.1

6) WP-Popular Posts Tool
Compatible up to 3.0.2

7) Popular Posts
Compatible up to 2.6.2

8) WordPress Popular Posts
Compatible up to 3.0.0

9) Most Popular Posts
Compatible up to 3.0.2

10) Popularity Contest
Compatible up to 2.8.0

When a new version of wordpress is released, many site owners find themselves being trigger happy and clicking on the upgrade link as soon as an upgrade is available. This is usually when most site owners experience issues. We have created a simple guide to help you to decide if your wordpress website is ready to upgrade.

1) Backup

Backup your website database and files. Many site owners do not create backups when they upgrade. If anything goes wrong during or after the upgrade, you will be left with no way to roll back the changes that have been made during the upgrade.

2) Plugin Compatibility

Go to the Plugins section of your wordpress blog and view your active plugins. Visit each plugin website, or if the plugin is listed on wordpress.org, you should search for the plugin and finally check the maximum wordpress version that the plugin is designed to work with. If the plugin is not designed to work with the wordpress version that you want to upgrade to, you should not upgrade until the plugin has been updated, or you find a new plugin that has the same features as your old plugin and works with the latest version of wordpress.

As you can see in the following image, we have located the plugin “Custom Author Permalink” on WordPress.org within their extend, plugins section. Here you can see that this plugin does not work with the latest version of wordpress. It has only been designed to work with wordpress 2.7 and under. The last update that was made to the plugin was almost 2 years ago!

While a plugin that has only been designed to work with a previous version of WordPress, it may not use many WordPress hooks and may well work with later WordPress versions. This is why WordPress.org added their compatibility feature, allowing users to vote and let everyone know which WordPress versions the plugin is known to work with. While this can not be entirely accurate, it can be used to gauge the probability that the plugin will work with your desired version of WordPress. However, as you can see from the following image, the plugin Custom Author Permalink has no users that have voted to say it is working with the latest or previous releases of WordPress.

When you find a plugin that does not work with the latest version of wordpress (or even your current version of wordpress), you should not upgrade wordpress, or you should find a new plugin to replace it.

What damage can an out of date plugin do?

If you are using a plugin that was designed for a previous version of WordPress, some, or all of its features may not work. It may cause conflicts with WordPress, other plugins, your theme or even new browser releases which it has not been tested with.

Remember, that not all plugins are available on WordPress.org. If you use a plugin that is not on WordPress.org, you should contact the plugin developer and ask them directly what WordPress versions the plugin has been tested with including any known bugs or issues.

We hope you found this guide useful. We see a lot of users upgrading without making any backups, only to find that the main and vital plugins used on their website no longer work and they have no way to roll back the changes they made during the upgrade.