How do I change the profile or account of the default login

When I first turn the PC on it attempts to login through what must be the default account held by Windows 10. That fails because the password doesn't match. So I'm at the login, I've forgotten the password. At the login screen there is a second user icon for which I do know the password. So I can login manually. This is OK but I want to login automatically.I figure I can delete the faulty login (if I knew the password) or make the second user icon the default profile or account. I'm not sure if this is a feature of my version of Windows 10 or not, but I haven't found anywhere within my system that enables me to reset my password. This has been frustrating. I've tried netplwiz but haven't had access to anything to make a change. I followed the TenForums Tutorial to guide me through the registry, where I looked at the ProfileList and although there were several profiles with S-1-5 type numbers there was only one profile which had a GUID long number. Apparently this means it is an active profile. I don't have enough confidence in this area to do anything with it. So, I'm hoping I can get some assistance to resolve this situation and hopefully be able to turn on the PC and have it login automatically and finish at the desktop.

It sounds like you don't have access to an account with administrator privileges. Open a command prompt or powershell (Press Win + X to get the list where you will find Command Prompt or Powershell) and run:
net localgroup administrators

What accounts are listed under Administrators? Is one of those accounts one that you can log into?

For example, the accounts on my computer that are administrators are Administrator (which is disabled by default in Windows 10) and John:

Code:

C:\Users\John>net localgroup administrators
Alias name     administrators
Comment        Administrators have complete and unrestricted access to the computer/domain

Members

-------------------------------------------------------------------------------
Administrator
John
The command completed successfully.

Hi NavyLCDR,
Thanks for the response. Our time zones makes for a delay in my response.
OK, I ran Command Prompt with the instructions you gave and it listed 2 Names, (unless the first one is a heading),
Administrator, like you said this one must be the one made by Windows 10, so maybe it is just the one?
David-Desktop

Now David-Desktop was the account where I mucked up the password, so Windows tries to login on this one but the password with this account is wrong, so it fails at the login. This is the account that Windows is supposed to login automatically (through unchecking the box in netplwiz). So I finish up at the login with a failed password. I can get in through using the PIN option, which is OK but not preferred. Then there is a second icon there at the login which I can select and enter the password which I do know for it, and that works. But this login must be the "Administrator" which was the other member in that list? I don't exactly know how this came about but it started out with me trying to rename the PC, instead of David-Desktop, this is where things became confusing, and I think mistakes were made.

I hope that a bit of background may have helped you know exactly what is going on with my PC. My goal/hope in all this is to be able to just login automatically when I turn the PC on and start doing stuff at the desktop. Thanks again.

I'm confused.... when you log in with a PIN, is it the David-Desktop account that is listed under Administrators? And do you know the password of that account?

Sorry to confuse you,

When the initial auto login fails, which I presume is the David-Desktop account, it offers me an alternative sign in option, the PIN, which I do remember, so I can get in that way.

Can I set the auto login to work on a PIN? I didn't think I could. The only other choice is to put in the password, which I can't remember.

When I'm at the login area, there are 2 icons down the bottom left hand corner. One of them is the default login, this is the David-Desktop login and I don't know the password for it.

The second icon is called "Dave" and I want it to be the default login because I know the password for it.

I'd also like to delete the David-Desktop profile, so there is only one login, but I'm not sure if the other login is an Admin account (the second icon). I went into netplwiz and David-Desktop is listed with Admin but the only other account shown there is HomeGroupUser, which doesn't have any Admin privilege, is this what the other icon called Dave is representing?

*** UPDATE ***

I just rebooted my PC and it didn't offer me the "PIN" option, but the account name in the username box is David-Desktop, so that is definitely the account that came up in Administrators search earlier. There were times when I clicked on "Sign in Options" that it did offer me the option of PIN but not this time.

As for the second icon that displays in that login area, I was able to supply it with a password and I can successfully login that way but I don't know much about this account, From the TenForums tutorial I looked at yesterday there looks to be only one active profile in ProfileList. I can't explain this second a/c other than I've accidentally created it, I know the password, but it doesn't seem to have any Admin properties. But I can login with it.

If you open a command prompt again and run:
net users

Code:

Microsoft Windows [Version 10.0.15063]
(c) 2017 Microsoft Corporation. All rights reserved.

C:\Users\John>net users

User accounts for \\JOHN-LAPTOP

-------------------------------------------------------------------------------
Administrator            DefaultAccount           Guest
John
The command completed successfully.

Administrator is the built-in Administrator account which is usually disabled by default. You can enable it with some registry hacking if you are not logged into an account with administrator rights. By default it has a blank password. We will get how to hack the registry in a minute.

DefaultAccount is an account you can't really log into. It just contains the template that is used when you create a new account.

Guest is an account that is also disabled by default. It is a very limited user - even more limited than a regular standard non-administrator user.

Any accounts other than those are user accounts that were created on the computer. So John is the only user account I have actually created on my computer.

In the command prompt you can run the command:
net user <username> (put a specific account name in place of <username>)

The last section of the user report will tell you if that account is part of the Administrators group or not:

Code:

C:\Users\John>net user John
User name                    John
Full Name                    John <redacted>
Comment
User's comment
Country/region code          000 (System Default)
Account active               Yes
Account expires              Never

Password last set            9/30/2016 6:55:07 AM
Password expires             Never
Password changeable          9/30/2016 6:55:07 AM
Password required            No
User may change password     Yes

Workstations allowed         All
Logon script
User profile
Home directory
Last logon                   10/1/2016 8:58:13 PM

Logon hours allowed          All

Local Group Memberships      *Administrators
Global Group memberships     *None
The command completed successfully.

If the account you can log into is not in the Administrators group, then you will have to enable the built-in administrator account, log into that and fix your normal user accounts. You need a bootable Windows 10 USB flash drive or DVD to boot the computer from and use option 4 here:
Enable or Disable Elevated Administrator account in Windows 10 - Windows 10 User Accounts Tutorials

Now I'm confused.
I ran command prompt net users and it displayed (Please let me know how to copy the cmd prompt output into that embedded code window), it showed:
User accounts for \\Dave
Administrator David-Desktop DefaultAccount
Guest

I then tried net user Dave
and it said username could not be found

I then tried net user David-Desktop and it came out with quite a lot of information very similar to yours. Command prompt doesn't let me copy and paste so I'd like to put all that info into this post. Anyway things it does say are,

User name David-Desktop
Full name Dave
Active account Yes
Account expires Never
Password last set 18-Apr-2017 3:30pm - (That's when things started to go wrong).
Password expires Never
Local group memberships Administrators HomeUsers
Performance Log Users
That's about it.
What is the "wash-up" from all this?
I'll make another post shortly.

Dave and Dave-Desktop appear to be the same user account. You can login in with a PIN. And it is an administrator. So, this is what I would do before you manage to lock yourself out...

Create a temp local account:
Add User Account in Windows 10 - Windows 10 User Accounts Tutorials

Change that temporary local account to an administrator:
Change Account Type in Windows 10 - Windows 10 User Accounts Tutorials

Log in to the temp local account you created, and run: netplwiz

In netplwiz you should be able to reset the password on the Dave-Desktop account.

In regards to your previous post where you recommended I read, Enable or Disable Elevated Administrator account in Windows 10 - Windows 10 User Accounts Tutorials
In that tutorial it wants me to boot from a Windows 10 installation USB or recovery drive (whatever that is). I don't have a Windows 10 installation USB, I have my DVD that came with the PC when I bought it, how do I make this USB? It recommends I have an 8GB, which I do have so that's cool.

Weighing up my options, and looking at the other tutorials you've recommended, I'm beginning to think it's quite a job ahead. Maybe I'd be better off simply re-installing Windows from scratch and pay more attention to what I'm doing regarding User A/cs. I certainly don't want this problem to happen again, what do you think? I would respect your opinion on this.

I don't know if I'm overstating what's ahead of me here. But I recognise you've put a lot of time and energy into trying to help me, which I'm very grateful for. I'll look into what is involved with making the USB (I don't know how to make one). I'll make another post later tonight (my time). Thanks.:)