can't log in to Oulook on my Windows PC

Try these checks in order:

1. Verify the username format. In Outlook, the username should be the full email address. A common cause of repeated password prompts is an incorrect username.
2. Check for typing issues. Passwords are case sensitive, so make sure Caps Lock is off.
3. If this is a Microsoft personal account, confirm the account can sign in on the web. Try signing in to Outlook.com first. If web sign-in fails too, use the account troubleshooter or recovery flow.
4. If the password works on iPhone but Outlook for Windows still rejects it, add the account again from the Mail profile.
   • Open Control Panel
   • Select Mail
   • Select Email Accounts...
   • On the Email tab, select New
   • Enter the name, email address, and password
   • Select Next and complete setup
5. If Outlook asks for an app password message such as "Please create an app password for Outlook on your email provider's site", get an app password from the email provider and use that in Outlook instead of the normal password.
6. If this is a work or school account and webmail also fails, the account may need help from the organization IT admin. Outlook support cannot reset work or school passwords or know the organization webmail settings.

If the sign-in issue is only with a Microsoft personal account, use these recovery options:

• Sign-in Helper
• Recover your account

References:

• Troubleshoot Outlook email setup
• How to sign in to Outlook.com
• I can't sign in to my Microsoft account
• My username and password have stopped working
• NoSuchAccountException: Login Error
• Add an email account to Outlook for Windows