mail won't send

If you are unable to send emails from your iMac or MacBook Air, but can send emails from web-based email, there may be an issue with the mail settings or configuration on your Mac. Here are a few things you can try to troubleshoot the issue:

1. Check your outgoing mail settings: Make sure that your outgoing mail server settings are properly configured. Open the Mail app on your Mac, click on "Mail" in the menu bar, and select "Preferences." Then click on the "Accounts" tab and select the account that is having issues. Make sure that the outgoing mail server settings are configured correctly, including the hostname, port number, username, and password.

2. Check your internet connection: Make sure that your Mac is connected to the internet and that your internet connection is stable. If you are using a Wi-Fi network, try resetting your Wi-Fi router or modem.

3. Check your firewall settings: Make sure that your firewall settings are not preventing your Mac from sending emails. Open System Preferences, click on "Security & Privacy," and then click on the "Firewall" tab. Make sure that the Mail app is allowed to receive incoming connections.

4. Try a different email client: If you are still unable to send emails from the Mail app, try using a different email client such as Microsoft Outlook or Mozilla Thunderbird to see if the issue persists. If none of these steps resolve the issue, you may need to contact your email provider's support team for further assistance.

I hope this helps! Let me know if you have any other questions or concerns.

Just remove the account and rebuild it from scratch. You get the credentials from the web mail's website. The same place/way you got them initially.