Fix Review Request Emails Not Sending in Sparkforge

By Sparkforge Support Team ·Last reviewed May 3, 2026

Confirm the SMTP sender matches the user sending the review request, validate any custom values render correctly in the email body, and account for Mailgun delivery delays before assuming the system is broken.

If review request emails aren't leaving the subaccount, the issue is almost always one of three things: a mismatched SMTP sender, a broken custom value, or a Mailgun delivery delay.

Step 1: Check the SMTP sender

Look at which SMTP address is connected under the subaccount's email integration. The user sending the review request must be logged in as that same address. If info@sparkforge.com is the connected SMTP sender, the request has to come from that user.

Step 2: Validate custom values

Open the review request email content and scan for custom values (merge fields). Confirm each one resolves to actual data on the contact — missing values can silently break the send.

Step 3: Account for Mailgun delays

Mailgun-routed sends can take a few minutes longer than direct SMTP. Wait at least 5–10 minutes before declaring a failure.

Frequently Asked Questions

Why does the SMTP sender have to match the logged-in user?

Most SMTP integrations only allow sends from the authenticated mailbox. If the logged-in user doesn't match the connected SMTP address, the provider rejects the send.

How do I check custom values in the email body?

Send a test from the review request settings or trigger the request against a real contact record and inspect the rendered email — any unresolved merge field will show as blank or as a literal placeholder.

How long should I wait before assuming Mailgun failed?

Wait 5–10 minutes. Mailgun queues sends behind reputation and rate-limit checks, so brief delays are normal.

Can I bypass SMTP for review requests?

Yes. If you remove the SMTP integration, Sparkforge falls back to the default mail provider — useful when troubleshooting whether SMTP is the blocker.