Installing and activating the Premium add-on is much like installing & activating any other WordPress plugin.
Since the Premium plugin depends on the free MailChimp for WordPress plugin, please make sure you have that installed first.
Activating MailChimp for WordPress Premium
Download the .zip file to your computer and login to your WordPress admin panel. It is not necessary to extract the .zip file.
Then, go to “Plugins > Add New” and click on the “Upload Plugin” link at the top of the screen.
You’ll be presented with the following screen where can you browse your computer for the .zip file you just downloaded. Press “Install now” and the MailChimp for WordPress Premium plugin will be installed.
After successfully installing the plugin, click “Activate plugin“ to activate the plugin.
That's it, you now have access to the Premium features of MailChimp for WordPress. Hooray!
Activating your license
If you want to receive plugin updates for MailChimp for WordPress Premium then you will need to activate the license key you received right after purchasing the plugin.
To do that, go to WP Admin > MailChimp for WP > Other and locate the "Plugin License Settings" section.
Copy your license key from the purchase receipt, paste it in the license key field and click the “Save Changes“ button.
In most cases, the plugin will detect the new license key and automatically activate it. If not, click the “Activate License” button to activate your license.
The plugin is now installed & configured to receive plugin updates. You're all set to grow your lists!