Fuga uses Mailgun to send your emails. As soon as an email address fails once — because it does not exist, a full mailbox, or a recipient marking your mail as spam — Mailgun adds that address to its blocklist. From then on, mail to that address is no longer delivered.
At the moment of sending you won't see an error in Fuga: Mailgun accepts the message, so the send itself looks successful. The mail simply never reaches the recipient. In the Sent mails via Mailgun report (Analyse => Reports => Sent mails via Mailgun) these attempts show up as failed, with the reason "Not delivering to previously bounced address".
With the Blocked email addresses report you can see which addresses are on the blocklist, why, and unblock the ones that can safely receive mail again.
Why are addresses blocked?
Blocking protects Fuga's sending reputation. When mails bounce or get marked as spam, the mail providers that receive them (Gmail, Outlook, and the mail servers of companies) start to distrust all mail sent through Fuga and treat it as spam. At that point even valid mails no longer arrive. By blocking the problematic addresses, Mailgun prevents this and keeps the rest of the mail deliverable.
SMS as a better alternative for reminders and confirmations
For appointment reminders and confirmations, SMS is a more reliable channel than email: it is not affected by spam filters or by the blocklist. For these time-critical messages, consider using SMS instead of (or alongside) email. See the SMS guide for how to set it up.
Where to find it
Go to Analyse => Reports => Show all reports => under Communication => Blocked email addresses.
What the report shows
For each blocked address you see:
- The name of the person
- The blocked email address
- The type of block: bounce or complaint (spam)
- The reason for the block
- The error code returned by the recipient's mail server
- When the address was blocked
- When it was last unblocked (resets when the address is changed)
- How many times it has already been unblocked (resets when the address is changed)
You can sort on the reason column, which makes it easy to find all "mailbox full" bounces together and unblock them in one go.
Block types
- Bounce — the mail could not be delivered (unknown address, full mailbox, server temporarily unreachable). These are usually safe to unblock once the cause is resolved, or when the address is actually correct.
- Complaint (spam) — the recipient marked your mail as spam. Do not simply unblock these. First contact the client through another channel and ask for their explicit consent to receive emails from you again. Only unblock the address once you have that consent — otherwise leave it blocked.
Unblocking an address
The unblock action is only available to administrator users. Click the unblock button on the row to remove the address from Mailgun's blocklist. From then on, emails to that address are delivered normally again.
An address can be unblocked a maximum of two times. After the second unblock the action is no longer offered for that address — at that point the address is genuinely problematic and should be corrected on the client record rather than unblocked again.
IMPORTANT
Sonetas monitors addresses that are unblocked and then get blocked again. Repeatedly unblocking an address that keeps failing or keeps being marked as spam harms the deliverability of email for all practices on the platform, and may result in Sonetas stopping your ability to send emails from Fuga. Only unblock an address when you are confident it can receive mail again.
Good to know
- Unblocking does not fix a wrong address. If the address itself is incorrect, correct it on the client record instead of unblocking.
- After fixing a domain/SPF problem, check this report and unblock the addresses that only failed because of that outage — they stay blocked until you unblock them.