I can't get in my laptop anymore. What to do?

I just wanted to go into my account, but forgot the password. I changed my password and wanted to sign up. Then came this message as seen in the picture. Was already on account.live.com but there I find nothing.

Just because you've changed your password for your MS-Live account, that's not changed locally on your PC. And that's exactly the problem right now. You would have to log in again with your old password.

That could be difficult, because I have now made the laptop after a year and a half again. I do not remember the password 3

In case of doubt, a new installation helps. If the disk is not encrypted, you can also access the data from another account or another system.