I will setup mx, dmarc, dkim, spf, dns records, smtp to improve email deliverability

SPF, DKIM, and DMARC are essential for robust email security and reliable delivery. SPF helps prevent email spoofing by specifying which servers are permitted to send emails for your domain. DKIM adds a layer of digital signatures to verify the email’s integrity.

fixing email authentication error is by checking credentials and verifying smtp setting

Mailbox providers no longer offer permanent whitelisting, so inbox placement can’t be guaranteed through manual approval. Instead, I focus on optimizing your email authentication (SPF, DKIM, and DMARC), removing any blacklist issues, and guiding you through tools like Google Postmaster Tools and Mic

An authentication email is a message sent by a service to verify a user's identity, typically containing a verification link or code to confirm that the email address provided is valid and belongs to the user.

Configuring email deliverability records usually doesn’t cause downtime. It involves updating DNS settings, which generally doesn’t impact email sending or receiving during the process.

Once your domain's SPF, DMARC, and DKIM records are set up, you usually don’t need to add extra DNS records for new email addresses. These domain-level records provide authentication and security for all your email communication, regardless of the specific addresses.