Forgot windows 10 login password after upgrade

[vgintaly]

I upgraded my windows 7 guest to windows 10 yesterday night. As usual, i added a login password for the machine. When I booted it up this morning, i found the password that worked before was wrong for now. I have a lot of downloads and files in that machine so i don't want to reinstall the os. Does anyone know how to regain the access to the machine without losing any data?

[Gloriarily]

If you still unable to login, then try with the below steps.

1. Restart your PC. When you reach the sign-in screen, hold the Shift key and select the Power button, and then select Restart.
2. After your PC restarts, select Troubleshoot > Advanced options > System Restore.
3. Select the restore point created prior to this problem and follow the on-screen instructions to restore your PC to earlier point of time.
4. Now try to boot your PC into normal mode and see if it works.
5. 
   

PS:  You could try resetting your Microsoft account's password and then try to use it to see if it works.  Otherwise try some third party free or paid windows password reset tools like Ophcacks, UUkeys windows password recovery and others if your forgot windows 10 password.

[vgintaly]

I am afraid this will cause data loss with this method. Any secure alternative?

[mackpt1]

Here is how to Reset your log in Password of The Windows 10

1- Open up the sign in page of Microsoft account from the web- Microsoft Sign in Page.

2- Towards the right, just below the text boxes for providing username and password, you will find Can’t Access your account? .Click upon it.

3- In the window that pops up, you will have to provide either your email id or phone number for verification purposes .Now, below it, enter the Captcha(either audio/text) as it is. Click on the Next button once you are done.

4- In the next window emerging out, click on the box which says Send Code.

5- Once you receive the link the verification security code in your email or phone number, type it in the box which requests for it.

6- You will now get a page to reset your password. Create a new one and remember it from now on for the login purposes.

Source:- https://merabheja.com/reset-your-log-in-password-of-the-windows-10/