I have a new Nextbook tablet that shows message "The contact doesn't exist" after tapping the user icon (top right of pull down menu). I am trying to change accounts, but I cant get to the user menu. I can access settings to see that I have two Google accounts on the tablet, but I can not access them from the user button to switch accounts.
To be more specific about the behavior when I tap the user icon: The screen flashes, click sound is heard and small message bubble shows with "The contact doesn't exist". The menu does not change to show users and add button.
adb shell pm get-max-users
. You would need adb setup in PC. // I've tested this theory once. I deliberately made my device support only single user. In that case, whenever I touched that user icon in pull down menu, I received that toast.