Q: How can I bulk email learners who have not completed a course?
A: If you have set up your course using the 'compliance settings' (see below) then there is an automated email that you can send out to all non-compliant users to hurry them along.
Find this menu item in the Course settings tab:
To send the automated compliance reminder email, click in to your Course as an Admin, then click on the People sub-tab, select the Learners that are not yet compliant, and from the drop-down on the right select 'Send compliance reminder email' (see below).
If you have not used the compliance settings and it is just a regular course where you want to chase up those people who haven't completed it yet, then there is no automated way to email only those people.
Instead you can go to the Messages area, type the name of the Course in the "To:" field and then write your message (see below). This way all learners assigned to the course will be messaged. It's important to note that this will include those who have completed it too, so you may like to word your email so as to direct it to just those who have not done it.
We covered this and other course actions you can do in bulk, check out How To: Manage People Settings Within a Course.