Not sure what you mean by "primary user".
You may possibly be able to add a user by going to settings/users and then add a user. The "primary user" will always be the one whose credentials were used to set up the device. Unless you want to factory reset the device and use your credentials to set up the device, you would likely only be able to add yourself as a new user.
PaPaEd, we're glad to hear that you found a new opportunity to use the Ellipsis 10! We definitely want to make sure that you're able to make the most of out of this experience.
In order to be able to properly answer your question, can you please elaborate on what you meant by "primary user"? The more information we have, the more we can be sure that we're on the same page as you. We don't want to steer you in the wrong direction.
Also, for future support you can always visit: http://vz.to/2pt5reG to learn more about using this device.
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