I recently found an old Samsung GT-C3322 that originally belonged to my dad and had been sitting unused for years. I turned it on to look through old photos and videos and experiment with the phone. I noticed that an email address I have used since 2020 appeared on the login screens for Windows Live Messenger, Yahoo, and Palringo.
I don't remember ever entering that address on this phone. It never had a SIM card while I was using it, and I mainly used it to take pictures, record videos, and transfer files over Bluetooth. I also had never used or knowingly installed Palringo. I did not do anything with the memory card until after noticing the email address.
Could this be leftover account data, autofill information, an imported profile, or something stored on the memory card? Is it possible that Bluetooth transferred the address somehow, or is there another likely explanation?
3 Answers
A previous owner or a past file transfer is more plausible than the phone somehow discovering the address over Bluetooth. Check contacts, browser history, saved form data, application folders, and the memory card for text or configuration files. Also consider whether another family member used the phone or card after 2020, since that could account for the newer email address.
The phone may not be the original source. Old feature phones and their applications could retain usernames in autocomplete databases, cached login pages, contacts, browser history, or restored application files. If the memory card or phone was previously used with another device, an account address could also have been copied there without you intentionally typing it into this phone.
It would help to identify exactly where the address appears. Seeing it as a suggestion in a login box is different from seeing it in a message, contact, browser page, or account settings. A login screen can display an old username simply because the application saved it locally, even if the account was never successfully used on this particular phone.

That would explain why the same address appears in multiple places, especially if those screens are reading a shared saved-credentials or contact database.