An end user is able to send emails but not receive them.

If a user can send email but cannot receive email, the most likely issue is with the incoming mail configuration rather than the outgoing mail configuration. SMTP is primarily used for sending mail from a client to a mail server (and between mail servers), so working outbound email strongly suggests SMTP settings are correct. To receive email, the client must connect to an incoming mail service such as IMAP (or POP3). Therefore, the first setting to verify on the laptop is the IMAP configuration, including the incoming server address, port number, encryption method (SSL/TLS), and authentication credentials. If any of these are wrong, the client may fail to synchronize the mailbox, making it appear that mail is not arriving even though messages exist on the server.

DNS can affect both sending and receiving because clients must resolve mail server hostnames, but when the symptom is specifically “send works, receive fails,” checking the dedicated incoming protocol settings is the most direct and likely fix. DMARC is an email authentication policy used at the domain level and is not a laptop-side setting the technician would check first for a single user’s inbound mail problem.