If your email isn't being seen, the problem likely isn't the copy itself. In foreign trade, when emails are rejected or land in the spam folder, most people's first instinct is to tweak the subject line or body text. However, the actual email delivery process is: Sending Server → Receiving Server → System Determination (Inbox/Spam/Blocked). The "delivery" phase occurs before the content is ever read. Issues like incomplete SPF/DKIM/DMARC configurations, poor domain reputation, or un-warmed IPs can "kill" the email before it even reaches the customer's eyes.

Step 1: Identify the real reason for rejection

Start by examining bounce codes and SMTP logs. Common reasons for rejection include: IP blacklisting, missing PTR records (reverse DNS), incomplete SPF/DKIM/DMARC setups, or reputation damage caused by sharing an IP with other users. Use online tools to check if your sending IP appears on blacklists like Spamhaus, and verify the consistency between your domain's MX records and the HELO/EHLO hostname.

Step 2: Complete the three authentication configurations

SPF acts as an "authorized list," telling the receiving server which servers are permitted to send emails on behalf of your domain. Without SPF, the receiving server may suspect identity spoofing and route the email directly to spam.

DKIM adds a digital signature to the email, allowing the receiving server to verify that the message hasn't been tampered with during transit. DMARC instructs the receiving server on how to handle emails that fail SPF or DKIM checks. For initial DMARC setup, it is recommended to use `p=none` to gather report data first; once you confirm all legitimate sending sources are covered, you can gradually tighten the policy.

For users self-hosting email services on Singapore-based servers, you must also configure PTR records (reverse DNS) for the sending IP and ensure the SMTP server's HELO/EHLO hostname is resolvable and matches the "From" domain in the email header.

Step 3: Warm up the IP—don't "blast 10,000 emails on day one"

Newly assigned IPs lack a sending history, so email service providers view them as unknown sources. Sending a massive volume on the first day will almost certainly trigger spam filters. A standard IP warm-up period lasts 2–4 weeks; start by sending a few dozen emails daily and gradually increase the volume while monitoring bounce and complaint rates. Warm-up recommendations: Segment your audience and stagger delivery times to avoid sending identical content in rapid succession; clean up invalid addresses and remove long-term inactive recipients; and monitor domain and IP reputation scores via Google Postmaster Tools.

Step 4: Choose a server environment that supports email services

Email for foreign trade businesses demands exceptionally high IP reputation. If a shared IP is compromised by the actions of other users, the cost of remediation far exceeds the expense of using a dedicated IP. Singapore-based nodes offer structural advantages regarding IP quality: IP ranges from Singapore data centers are less frequently blacklisted by international anti-spam organizations, and native IPs generally achieve higher email delivery success rates.

Tests on Jtti Singapore cloud servers confirm that Port 25 is open, making them suitable for hosting SMTP mail servers. All plans come with a dedicated IP as standard, preventing reputation cross-contamination associated with shared IPs. For foreign trade enterprises requiring self-hosted email services, we recommend a configuration of at least 2 vCPUs and 4GB of RAM, paired with 5Mbps of dedicated CN2 bandwidth, to ensure efficient mail queue processing and connection stability. Starting at $29.09 per month, this is more cost-effective in the long run than using third-party SMTP relay services.

Quick Checklist:

- SPF record configured and includes all authorized sending server IPs

- DKIM signature enabled and successfully verified

- DMARC record added (initially set to `p=none`)

- PTR record (reverse DNS) set up

- IP warm-up plan executed (gradual sending over 2–4 weeks)

- Bounce rates and complaint rates being monitored

For further technical assistance, please contact Jtti’s technical support team; our professionals provide 24/7 support to all Jtti users.