The mail server settings (the SMTP, POP and IMAP settings) can be used to connect a email account on a server, to a email client. This page has articles on how to find the mail server settings for most major email services.
Consumer Email Services
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Gmail
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Outlook
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Yahoo Mail
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Mail.com
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Zoho Mail
Business Email Services
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GSuite/Google Workspace – Gmail
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Outlook
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Zoho Mail
Self-Hosted Emails
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cPanel
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Plesk
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