The answers on this page are not getting at the problem. I too have now encountered “wrong password” when trying to log in after computer has been sleeping. I’m 100% sure the pwd is correct (same one for a decade, no chance of being wrong). No one has mentioned this, but in my case I’m using an EXTERNAL keyboard. When I use the computer’s built in keyboard, I can log in fine. I have not changed my external keyboard in years, and it’s been working fine for years up till two days ago. As others have said, I can also log in using the on-screen keyboard. The fact that I can log in either of these two ways implies clearly what the problem is (in my case anyway): it has to do with the external keyboard.
This is clearly yet another bug introduced by the brilliant Microsoft Windows team. I’ve checked the drivers for my keyboard and Windows thinks I already have the latest drivers. So now, I’m completely at a loss. I have to log in with the built in keyboard apparently. Thanks Microsoft, for another blunder.
Hope this helps others: if you’re using an external keyboard, try logging in with the built-in one, or use the on-screen keyboard. Both ways work for me.