Please follow these steps to resolve:

1. At the error message, click on Try Again
2. On the page that loads next stating the device is managed by SAU16, please click on the blue words "sign in with a different account"
3. Now sign in on the screens that follow.
4. Once logged in, please click on the area with the clock/wifi symbol and select the "gear icon" which will open up settings
5. Once that window opens, click on "About Chrome o/s" on the bottom left
6. Click on "check for update"
7. Once this completes, please restart the Chromebook and it should be all set