Many Windows 10 users come across the login problem due to an incorrect password, and don’t know what to do with it. Sometimes, but not always, your entered password is indeed correct, but Windows 10 says your password is incorrect. Though trying many times, it is still the same thing. This usually happens when the computer wakes up from Sleep mode, and may happen to local account or Microsoft account. Even some people report that password stops working after updating or upgrading to Windows 10. I suppose this might be a bug in Windows 10 that remains to be solved. However, before Microsoft solves this problem, you can try to fix it by yourself. After all, you can't log in to your Windows 10 before the problem is solved.
1. After you finish entering the password in the Password field, click the Reveal button that looks like a human eye at the right end of the Password field to reveal the password, so that you can check if your entered password is indeed correct more clearly. To make sure you can enter your password accurately, you should make sure the Caps Lock on your keyboard is not ON, make sure the Number Lock is ON, and make sure you are using the correct language if your keyboard supports multiple languages.
2. After checking, if everything is right but still Windows 10 says your password is incorrect, restart Windows 10, and see if the password works.
3. If the password incorrect problem is still not solved after Windows 10 restarts, now you have to change your Windows 10 account password.
If Windows 10 says password is incorrect when you are using your Microsoft account to sign in, you can simply change Microsoft account password on account.live.com/password/reset, by using another device. Once password is changed, use the new password to sign in to your Windows 10.
If Windows 10 says password is incorrect when you are using a local account to sign in, you have to change the password with a bootable USB flash drive. Here are steps.
You have been lost access to your Windows 10 computer due to incorrect password, so you need to use another Windows computer to create a bootable USB drive.
1. Download the Windows Password Refixer utility on another computer. Install and then launch it on this computer.
2. Insert a USB flash drive to the USB port on this computer, and follow the Windows Password Refixer screen to burn it to the USB drive.
3. When the burning is successful, a bootable USB drive is created, and you can pull the USB drive out of this computer.
Insert the USB drive to the Windows 10 computer that reports your password is incorrect, and boot the computer from the USB drive. After the computer successfully boots from the USB drive, the Windows Password Refixer screen will appear.
1. Click Windows 10, click the user account whose password is considered incorrect by Windows 10, and then click the Reset Password button.
2. Click Yes when asked if you want to set the password to blank. Then your password will be changed to blank.
3. Click Reboot, click Yes and quickly disconnect the USB drive from the computer.
4. Then, the computer will restart normally. This time you can rest assured that Windows 10 will not say your password is incorrect and that you can sign in without password required.