Hi Jim_615,
Thanks for your post in Microsoft Community.
I'm Mosken, I do apologize for the inconvenience that you're experiencing right now, let me help you sort things out.
According to your description, I knew that you want to change the guest account name because your administrator account name is the same as the guest account name, so it's difficult to distinguish which account you log in. If my understanding is wrong, please correct me in the reply.
Open "Run" by "Win" logo key + "R", enter "Control", open "Control Panel", and enter the same path according to the following picture.
If you are logged in as an administrator, you can select "Manage another account" on this page, then select the guest account and change the name.
If you are logged in as a guest account, just click "Change your account name" to change your name.
I wish the above will be helpful to you. Please feel free to let me know how it goes, and I will do my best to help you.
Best Regards,
Mosken - MSFT | Microsoft Community Support Specialist
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