What is API Admin and what purpose does it serve in Hosting Controller v10?

Question: What is API Admin user and what are the implications of deleting it or changing its password ?
Answer: Hosting Controller Primary installer creates multiple schedulers under TasksSchedulers on the HC Control Server. See below screenshot depicting the scheduled tasks added by Hosting Controller Primary installer:

API Admin is responsible for managing all these ScheduledTasks related to HC10 because all these tasks run under API admin user’s permissions and this user has rights specific to those methods and endpoints which are exposed in the HC10 API. Deletion of the user or modification in its password will result in the malfunction of the scheduled tasks related to Hosting Controller.
Caution: Never delete API Admin or change its password because this may result in malfunction of the control panel.
Case # 1 ( Deletion of API Admin user and how to rectify the problem ) : If API Admin user is deleted mistakenly then you can recreate the user in HC panel and re-assign it to HC Control Server by following the steps below:
Add API Admin user from: Panel Users >>  Staff Members >> Add Staff Members

Next assign this new API Admin user to HC Control Server by navigating to Configurations >> Control Server Manager >>  Control Servers, here assign new API Admin user by clicking "Change API Username" button.

Case # 2 ( Modification in the password of API Admin and how to rectify the problem) : If someone modifies the password of API Admin user mistakenly then tasks must be updated again from the Control Server by opening "Manage General Operations" and "Manage Advanced Operations" at Global Admin level and then resaving these tasks by clicking the "Save" button. View the screenshot below to learn more about how to update the tasks ( General and Advanced operations) at Global Admin level in HC10 panel :

If the problem still persists contact support@hostingcontroller.com for further assistance. View HC user structure in detail.