To resolve Windows password issue, you need to first check these points -
If you can’t login to your Windows OS then it might be possible that you are entering the wrong password. Although Windows passwords are case-sensitive so you have to capitalize each letter.
If you forgot Windows password then you can reset your password either with a password reset disk or by using the administrator account.
If your computer is in a workgroup then anyone who has administrator account can change your password.
If you are logging via wrong user account then use “switch user” to choose the right account.
If you are unable to start up your system normally then run System Restore in safe mode that is described as -
Log into your Windows and then go to Start> Help& Support > Performance & Maintenance.
Then click on option “Use System Restore to undo changes”. Then run the System Restore Wizard.
Navigate to the Welcome to System Restore Screen. On the same screen, you have to choose the option “Restore my computer to previous version”. Hit Next.
Move towards select a restore point screen. On this screen, you have to click on the most recent system checkpoint. Then click a restore point list and hit Next.
Now a system restore message will appear on the screen that list the configuration changes. Click OK.
Next, head towards Confirm Restore Point Selection screen. On this screen, press a click on Next. Now System restore will restore the previous Windows Configuration and restart your operating system.
Now, login into your operating system as an administrator. The System Restoration Complete screen will appear and if your problem does not get resolved then contact experts.