What is the "Add a mailbox using DNS Records" option?

It lets you use any email address on a domain you own (for example support@yourcompany.com) without signing in to Google or Microsoft. You enter the address, add a few DNS records to your domain so Deskhero can safely send emails on your behalf, and set up email forwarding from your existing email provider to a Deskhero forwarding address so incoming emails reach Deskhero and become tickets.