Set-up email address persists after creating local account

I set up a new Windows 11 laptop a month ago, for a family member. I used my own email address to do so. Then I created a local account and deleted the account which I'd used to set up the laptop. I have also deleted all associated devices while logged into my email account on my own computer.

But on the new laptop when I install new programs and they sometimes ask for name or username, auto-fill shows my email address. Okay, I can delete it and type what I want. But somewhere deep down my email address is stored on the laptop despite me having deleted the user account it's associated with. I find this irritating as well as baffling. Tried all settings - no luck. How can I purge the new laptop of my email address?

Btw, I have never logged into my email account while using the new laptop.

(Also, when I set up the laptop, I used an alias email address. But the laptop basically used my main email address instead of the alias. Before I created the local account, my main email address was shown when logging in. And the autofill now shows that main email address.)

Hello David, and welcome to the forum.

You can double check Accounts used by other apps on your laptop using the tutorial below to see if your Microsoft account may be listed there to remove.