Q: An old email address keeps popping up on Windows OS computer

I think this Apple article    ☞  What to do after you change your Apple ID email address or password need to be update.

Mac with OS X Mountain Lion or later, or Windows PC.

1. Go to the Apple Online Store.
2. Click , then click View Account.
3. In the Account Settings section, click "Update your Apple ID email address and password."
4. Enter your updated Apple ID and password.

After Apple event the link Apple Online Store show new Apple products ; also on a Mac computer.

To view my account from Windows OS 10 (also on my Mac), I start iTunes on the computer.

Then click iTunes Store tab and View My Account.

FYI: I have changed my Apple ID a long time ago, no problem on the Mac .

Just to day want to use it on the Windows computer and my old emailaddress keeps popping up.