User account disappeared

[NicolaCalvert]

After being locked out of my account I tried to add a new user on the cmd prompt so I could gain access to reset my password however when I try to sign in to the new account it say 'user sign in failed to load', I tried to change my password via cmd prompt as well but it comes up with 'an internal error has occurred ' and now my original account has disappeared off the login screen altogether I can not do a clean install as I have work on there that I need! Any ideas n how to just gain access?? I have got a new HDD coming anyway for Christmas so I could potentially do a fresh install on there however because I upgraded from Windows 7 to 10 I'm not sure it will allow it onto a new hard drive?

 

[Trouble]

Hello and welcome to the forum.

I have got a new HDD coming anyway for Christmas so I could potentially do a fresh install on there however because I upgraded from Windows 7 to 10 I'm not sure it will allow it onto a new hard drive?

That shouldn't be an issue, assuming that you were running Windows 10 on the machine and it was already activate, then a clean install on a new hard drive should not be a problem.

Any ideas n how to just gain access??

There are a couple of methods that you could use to enable the hidden administrator's account, thereby giving you some access to your computer and files to rescue your data and correct issues with a problem user account or create a new account.
https://www.windows10forums.com/threads/keeps-saying-incorrect-password.1185/#post-12550
ALSO
http://pureinfotech.com/2015/11/20/how-reset-windows-10-forgotten-password-regain-access-computer/
They both involve using the installation media to boot your system and then using the advanced troubleshooting options to get to a command prompt.
I've used the first method and know that it works, I haven't had a chance to play with the second method yet.
The installation media can be obtained through either of these two resources.

https://www.microsoft.com/en-us/software-download/techbench
OR
http://www.microsoft.com/en-us/software-download/windows10

Once you have the ISO, you can use ImgBurn to burn it to a DVD or Rufus to burn it to a USB ThumbDrive, either of which you can use to boot your computer.
When you've managed to boot from the installation media you need to click the Repair Your PC link on the second page after the Choose a Language and Keyboard layout page.
That should get you to the Advanced Troubleshooting options.

A third possible option would be to boot from a Linux Distro Live CD (DVD or USB ThumbDrive)

 

[Trouble]

I've used the first method and know that it works, I haven't had a chance to play with the second method yet.

I just used the second method and it works fine as well and is a bit easier to do than the first option.