Hello! Thank you for your question. I am a licensed computer professional with over ten years of experience, and I will be assisting you today.
I'm sorry about the issue. Does this laptop have windows 8? Do you remember your Microsoft account / email address? Do you need any data / file on this laptop? On the working computer, can you go to the website http://account.live.com , and sign in your microsoft account / email address?
If that does not work, at the log in screen, press & hold the Shift key on your keyboard, then click on the Power icon, then click on Restart, then until a menu appears, then release the Shift key, then select the Troubleshoot / refresh... option.
It looks like you are away, please reply back when you are available to continue. Thank you,