CompTIA Network+ (N10-007) — Question 470

A network administrator migrated the data for the corporate email service from one provider to another. All DNS records were successfully changed and verified.
However, many hours later, users are still receiving new emails on the old provider's server. Which of the following should the administrator perform NEXT to troubleshoot the issue?

Answer options

• A. Add a secondary MX server to the DNS records.
• B. Remove old SPF records from the DNS host.
• C. Create a DMARC record that includes the old server.
• D. Check the TTL value on the MX records.

Correct answer: A

Explanation

Adding a secondary MX server to the DNS records can help ensure that emails are properly routed to the new provider. The other options may not directly resolve the issue: removing old SPF records won't stop email routing, creating a DMARC record for the old server isn't necessary, and checking the TTL value may not provide immediate resolution to email delivery problems.