Hi Annie. I'm Greg, 10 years awarded Windows MVP, here to help you.
Here is how to reset the password:
https://www.tenforums.com/tutorials/14699-reset...
If you are unable to reset your password by any means and have no other Admin accounts to sign into, then you'll need to Reset the PC. See here how to Reset the PC from the Sign-in Screen:
https://www.addictivetips.com/windows-tips/how-...
Do a deep clean reset saving nothing, so it has you create a new account or you won't be able to sign into the old account if you do a reset saving files. Also choose the Cloud Reset so it downloads the latest installation files and doesn't use possibly corrupt onboard files that will cause it to fail.
If the Reset from the Log-in Screen doesn't work, then Use whichever method works here to get into Repair Mode so you can try another Reset:
https://www.tenforums.com/tutorials/2294-advanc...
Easiest is to force shutdown by holding in the power button to cut the power, do this 3 times until it starts into Repair Mode.
Then choose Troubleshoot Options > Reset, then Deep Clean Reset (not saving files) and cloud option to download fresh files for reinstall instead of using possibly corrupted onboard files that often fail.
It may be necessary to create bootable media on another PC to access Advanced Startup Options to do a Reset or do the Clean install. Booting into the media is the only method that doesn't require a password and has it's own set of Windows files so the Reset might work better, and if not you'll have it to do the vastly superior Clean Install.
To create Windows 10 Installation Media on another PC install Media Creation Tool and follow the directions here:
http://windows.microsoft.com/en-us/windows-10/m.... Uncheck the box for Recommended Settings to choose the exact version and bit rate for the target PC only.
Insert media, boot it by powering up PC while pressing the BIOS Boot Menu Key given here:
https://www.sysnative.com/forums/hardware-tutor...
If the media won't boot you may need to enter BIOS/UEFI Setup (pressing key given in chart in link above) to turn off Fast Boot or Fast Startup first.
Choose the boot device as a UEFI device if offered, on second screen choose Repair Your Computer, then Troubleshoot Options to try a Reset. Make sure to choose a Cloud Reset if offered so it downloads fresh files first, also do a Deep Clean Reset which is cleaner but doesn't save your files. .
If that fails choose Install Now, then Custom Install, then at the drive selection screen delete all partitions down to Unallocated Space to get it cleanest, click Next to let it create needed partitions and start install - this makes it foolproof. Everything needed to get the best possible Clean Install is here:
http://answers.microsoft.com/en-us/windows/wiki.... It is a better install than any amount of money can buy and a great learning experience that will make you the master of your PC because you will learn what works best and how to apply it with your own hands.
If you have files that aren't backed up you can use the same bootable media to try to rescue your files using these methods:
http://answers.microsoft.com/en-us/windows/wiki...
I hope this helps. Feel free to ask back any questions and let us know how it goes. I will keep working with you until it's resolved.
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