Can't log in....Help please!!

When computer starts up it has the screen showing date and time. As soon as I touch any key, a green screen with email address pops up. It wants me to type in password. Once I type the password in it tells me my PC is offfline. Please sign in with the last password used on the PC. I have no desktop, nothing. Just goes back and forth between these two screens. What do I do???

Thank you in advance for any help anyone can give me.

did you type in the password for that email acct ?