Can I remove an inactive user from a course?

You can do this by deleting the user's enrollment, however the user must first be made active. Company Administrators can make this change from the Administration section:

1. Select Manage Users
2. Search for your user and select Edit Profile from the Actions menu on the right-hand side
3. Under User Properties check the User's Account is Active box, then Submit your changes 
4. Click on Current Enrollments on the left-hand side
5. Check the box next to the enrollment you wish to remove
6. Click the Delete Enrollment(s) link, then click Submit on the next page to remove the enrollment