Q: iMac repeatedly asks for login password despite automatic login being enabled

My Mac requests a login password both at startup and whenever the computer is idle for a short period of time despite the fact that auto login is enabled. This has only been occurring after the last update to El Capitan.  I have read the other support posts regarding this issue but none of the suggested solutions work:

- My system/admin password is different from my Apple ID/iCloud password

- I have not selected "use iCloud password" for the system login

- I do not have File Vault enabled

- "Require password after.. sleep or screensaver" is unchecked