Can't logon Windows 10

a weird issue with my brand new PC. Loaded with Windows 10 Home. After upgrading to Windows 10 Pro, all went well at first.
Then bring machine to site, put on network usual way - all good. Reboot PC, try to login as user, but receive incorrect username/password message.
How to resolve this issue?
Then bring machine to site, put on network usual way - all good. Reboot PC, try to login as user, but receive incorrect username/password message.
How to resolve this issue?
Comments
On another computer, go to Microsoft’s Sign in page. Once there, enter your email address and click Can’t access your account.
If this is your local account, you can try to create bootable USB reset tool.
NTpassword:
ht://pogostick.net/~pnh/ntpasswd/
Ophcrack:
phcrack.sourceforge.net/
or UUkeys windows password recovery.
http://www.uukeys.com/reset-windows-10-password.html
but I firstly suggest you try NTpassword.
https://4sysops.com/archives/forgot-the-administrator-password-the-sticky-keys-trick/
http://www.top-password.com/blog/reset-windows-10-password-with-sticky-keys/
Or use the free live cds - Hirens' bootCD, Ubuntu Live CD, etc.
You can reset windows 10 administrator password on command prompt with an available admin account to enter safe mode first. If you have another Windows 10 admin account, try these steps below:
Step 1: Press F8 when your Windows 10 PC is booting. You will come to the Advanced Boot Options. Then choose Safe Mode with Command Prompt and press Enter.
Step 2: Enter safe mode with an available admin account.
Step 3: Type "net user" and press Enter. The command prompt will show you all accounts on the Windows Vista PC.
Step 4: Type "net user Paul 123" (Paul is the locked admin account's name and 123 is the new password) and press Enter. Now you have successfully created a new password on the locked admin account.
Step 5: Type "shutdown -r -t 00" and press Enter.
Your Windows Vista PC should be rebooted automatically and then you can logon Windows Vista with the new password.
As I said before. i change the first boot drive to be a DVD ,all over again , after i startup my computer , the DVD flash drive can be identified,
Thanks for your suggestion ,This is very helpful for people who are not skilled in computer technology.
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