Unable to change Outlook out going mail STMP to mail.iquest.net

For classic Outlook on Windows, update the outgoing server settings through Mail in Control Panel:

1. Open Control Panel.
2. Open Mail.
3. Select Email Accounts.
4. Select the account, then choose Change.
5. Verify the Incoming mail server and Outgoing mail server values match the settings from the email provider.
6. Under Logon Information, verify the User Name and Password are correct.
7. Select More Settings > Advanced.
8. Compare the Outgoing server (SMTP) port number and encryption type with the provider’s required settings, then correct them if needed.
9. Select OK, then Test Account Settings.

If the SMTP password still fails:

• If the password was changed recently on the email provider’s website, update it in Outlook as well.
• If the provider uses two-factor authentication, Outlook may require the generated passcode or an app password instead of the regular password.
• If classic Outlook keeps prompting for the password, confirm Caps Lock is off and the username is the full email address.
• For SMTP send failures, also check More Settings > Outgoing Server and enable My outgoing server (SMTP) requires authentication, using the same settings as the incoming mail server.
• If Test Account Settings shows red markers, the settings are still incorrect and the email provider must verify the correct SMTP server, port, encryption, and password method.

If Outlook 2016 is being used and the password contains Unicode characters such as ä, ö, or ü, authentication can fail with IMAP. Change the password so it does not contain Unicode characters.

References:

• Change or update email account settings in Outlook for Windows
• Troubleshoot Outlook email setup
• I can't send or receive messages in Outlook
• Authentication fails when you use an IMAP server in Outlook 2016
• Trying to set up emails and the login to IMAP server completes ok but the SMTP server fails. - Microsoft Q&A