Instructions:
How to get admin access:
1.) Boot into safe mode. You can do this easiest by opening a command prompt (start menu -> type 'cmd'). And type "shutdown /r /o".
2.) You computer will begin to restart but give you a set of troubleshooting options. Choose Troubleshooting -> Advanced Options -> Startup Settings.
3.) After restarting and entering safe mode, switch users by going to the start menu -> click your username -> and choose Administrator.
4.) Windows will begin the first-time initialization for this account.
5.) Once logged in, open the command prompt again, this time as an admin. (Right click -> Run as Admin).
6.) Type "net user Administrator /active:yes" To set the admin account as "active". It will now show up outside of safe mode.
7.) Reboot your machine and log in as the admistrator again. You can now add users and play with permissions etc. (The metro options are not available in safe mode, hence the reboot).
How to remove your old 'lost' account and sync your new account with microsoft account.
1.) Create a new account via the users section from the control panel. Be sure to give yourself admin rights.
2.) Delete your old lost account by typing "net user <username> /del" into an administrator command prompt. You need to know your old account name, good luck with this one.
3.) Go to your pc settings: Open the right-side context menu -> Settings -> "Change PC Settings".
4.) Go to users tab -> Select "Switch to a Microsoft Account".