Reset the mailbox password on your email provider’s website first, confirm that the new password works in webmail, and then use that password when classic Outlook displays “Sign in required — Sign in to resolve.”
1. Recover the correct mailbox password
- Open your email provider’s website in a browser—Gmail, Yahoo, or the company that supplies your address.
- Try signing in with your full email address and current password.
- If it fails, select the provider’s Forgot password or Reset password option.
- Complete the provider’s account-recovery process and create a new password.
- Sign out of webmail, then sign in again with the new password to confirm it works.
The password cannot be reset from Outlook; third-party passwords must be changed through the email provider. ^1^
2. Sign in again through Outlook
- Open classic Outlook.
- Select the Sign in required notification.
- If a provider sign-in page opens, enter:
- Your full email address
- The newly confirmed password
- Approve any provider permission request needed to connect Outlook.
- Allow Outlook a few minutes to synchronize. If it does not resume immediately, close and reopen Outlook once.
Passwords are case-sensitive, so check Caps Lock and ensure the username is the complete email address. ^2^
If the provider asks for an app password
Only use an app password if the provider or Outlook explicitly says one is required. Generate it on the provider’s account-security page, then paste that generated password into Outlook instead of the regular mailbox password. ^3^
If webmail works but Outlook still does not
- Look at the bottom of Outlook. If it says Working Offline, select Send/Receive → Work Offline once to return online.
- If it says Disconnected or Trying to connect, confirm that ordinary websites open in your browser.
- Do not remove the email account yet. First note any exact error code shown under Send/Receive → Show Progress; that code determines whether the next step is credential repair, account-setting repair, or profile repair.
References
- Change or update your email password in Outlook for Windows | Microsoft Support
- Troubleshoot Outlook email setup | Microsoft Support
- [New Outlook](https://support.microsoft.com/outlook/i-can-t-send-or-receive-messages-in-outlook#have-you-changed-your-password-recently)