Unable to Create a New User in Salesforce Starter (formerly Essentials)

This is likely due to your organization not having free or available licenses. In order to create new users you would need to purchase an additional license. You can do this by clicking the gear icon in the upper right and go to Manage Subscription.

As a workaround, if you have a user license assigned to someone that is no longer with your organization or no longer needs access to Starter (formerly Essentials), you can deactivate them to free up the user license. 

1. Click the gear icon in the upper right and click Setup
2. In the left navigation expand Users
3. Click Users
4. Click the drop-down to the right of the user you want to deactivate
5. Click Edit User
6. Deselect the Active checkbox
7. Click Save

Once a user has been deactivated, please allow a few minutes for the system to register this change and free up the license on the back end before attempting to create the new user.