MyBB plugins and additional functionality
In order to install a plugin for MyBB there are 2 two general things you should do. Upload the plugin, then activate it from the administrator backend. Please note that different plugins may need you to make additional modifications. This will be included in the plugin documentation provided by the author.
Here are step-by-step instructions how to install a new plugin for MyBB:
Step 1 Upload the plugin file (the file format will be something like: pluginname.php) to inc/plugins/ folder located under the root of your MyBB installation. Note that it is imperative not to change the file name.
Step 2 Log in to your Admin CP and click on "Plugin Manager" in the Settings category of the menu.
Step 3 Click "Activate"for the plugin you have uploaded.
Step 4 In case everything is in order, you will be redirected to the plugin manager and the button for the plugin will change to "Deactivate. You can use it to stop the plugin from working on your MyBB installation.