On chromebooks, I've had students turn off their wifi, click the sign-in button a few times, turn their wifi back on, and then click the sign-in button, which works! I can't explain why, but it's been effective!
On chromebooks, I've had students turn off their wifi, click the sign-in button a few times, turn their wifi back on, and then click the sign-in button, which works! I can't explain why, but it's been effective!