El Capitan: Cant Change Subuser Password Under Admin Account

[phuturebot]

I have tried the initial test of changing password for the username using command R at Startup.
Creating a new password, saving, and restarting to no avail.

I tried logging in as Admin and changing the User password under systems prefs. It says it is changed but then after rebooting, new password still does not work. I was recommended to log in under safe mode from a Mac advisor but that didn't work.

I noticed the User is a "sharing only" account and has no option to change to an admin. I am thinking this might be fix the issue but there is no way to convert the sharing only account to an admin account. The only options available is the Reset Password button. How can I safely change my user account to an admin account- when I click Advanced Options I get a warning that changing any of those settings can disrupt that user and damage the account. I read online that the login shell would have to be changed but I have no idea what that means and don't want to tamper with that option unless I know it won't mess my user account up.

 

[DeltaMac]

Something has caused your admin account to change to another type of account. Likely a glitch from a system update, or some weirdness from a security update.
If you don't have another account that is admin, you can't change your existing account to an admin account, because you don't have an admin account, and then you just run in circles until you find a way to re-add an admin user to your system.

It happens occasionally, and can be fixed

Here's a site that can help you fix that. It will show you how to reset the setup assistant (which runs when you set up a brand new Mac.)
After doing that, follow the steps to add a new account to your Mac. Do NOT name it the same as your real account (the one that you want to keep!) This is just a temporary account, which will be an admin, and with that you can change your real account back to an admin.

When you create your new account be sure to check the box that says something like "allow this user to administer this computer". Log out, then Log in to that new user.
Once logged in, you can then change your real account to an admin account. Look for that same checkbox "allow to administer", etc.
Then, after changing your real account, you can log out, then log back in, and everything should be in good order now.
And, finally, you can delete the other, new user account, if you want to do that.