Fixing an unknown collation: 'utf8mb4_unicode_ci' error

I've been trying to migrate a wordpress site onto a very old IIS server, and keep coming up with an error when importing the database into phpMyAdmin:

#1273 - Unknown collation: 'utf8mb4_unicode_ci' 

Fortunately the issue is fairly easy to fix. In phpMyAdmin of the source website:

1. Click the "Export" tab for the database
2. Click the "Custom" radio button
3. Go the section titled "Format-specific options" and change the dropdown for "Database system or older MySQL server to maximize output compatibility with:" from NONE to MYSQL40.
4. Scroll to the bottom and click "GO".