This usually points to a display name, alias, or account configuration issue rather than a Windows update changing the actual mailbox owner.
Try these checks in order:
- Check whether the wrong name is only a display issue
- Send a message to another address controlled by the account owner.
- Open the sent message and inspect whether the sender address is still the correct email address and only the name shows as “USAA Support.”
- If the email address is correct but the name is wrong, the problem is likely the account display name or a cached/contact entry.
- Check the Microsoft account alias and account info
- Go to Edit account info: https://account.live.com/names/manage
- Review the email aliases on the Microsoft account.
- Remove any unfamiliar address if present, or add/update the correct address as needed.
- Microsoft states that aliases share the same account, password, contacts, storage, subscriptions, and settings.
- If using Outlook for Windows, verify the account settings
- Open Outlook > File.
- Under Account Information, select the affected account.
- Select Account Settings.
- Check Account Name and Sync Settings and Server Settings.
- In Server Settings, verify the login information, password, server name, port, and authentication settings.
- Select Next > Done after correcting anything incorrect.
- If needed, verify from Mail in Control Panel
- Open Control Panel > Mail > Email Accounts.
- Select the affected account > Change.
- Verify the Incoming mail server, Outgoing mail server, User Name, and Password.
- Select More Settings > Advanced.
- Check the IMAP/SMTP port numbers and encryption types.
- Run Test Account Settings.
- Red markers mean settings are wrong; green check marks mean the account is configured correctly.
- If Outlook shows a strange sender identity after account setup
- There is a known Outlook for Windows issue where a mailbox can appear with an unexpected sender format after adding certain accounts.
- The documented workaround is to create a new Outlook profile and set the account up manually as IMAP or POP:
- Close Outlook.
- Press Windows key + R, run
outlook /profiles.
- Select Options > New.
- Create a new profile.
- Choose Advanced options > Let me set up my account manually.
- Enter the account password and complete setup.
- If setup fails, use the server details from the email provider and finish the profile setup.
- If the wrong sender appears in Outlook on the web too
- That points more to the account identity or alias rather than the Windows app profile.
- Review the Microsoft account aliases first.
- If sign-in or account details cannot be changed
- Use the guided support tool linked from the Microsoft account alias page.
- Microsoft also provides Contact Support from the account support page for account-change issues.
If the sender address itself has changed to an unfamiliar address, stop sending mail until the account aliases and account settings are reviewed.
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