It sounds like you're experiencing an issue with your email account on your iPhone after changing your password on Outlook.com. This can happen due to a limitation with the Exchange ActiveSync protocol when using basic authentication. Here are some steps you can take to resolve the issue:
- Check Email Profile Settings: Ensure that your email profile on the iPhone is set up correctly. Sometimes, you may need to remove the account and add it again with the new password.
- Enable OAuth: If your email solution supports it, consider enabling Open Authentication (OAuth) in the email profile. This can help with password prompts after a change. However, make sure that your email service supports OAuth before enabling it.
- Use Microsoft Support and Recovery Assistant: If the problem persists, you can use the Microsoft Support and Recovery Assistant tool to diagnose and fix issues with sending and receiving emails. This tool can help identify connectivity issues and guide you through the resolution process.
If you continue to face difficulties, you may want to reach out to Microsoft support for further assistance.