Read the bounce log from the campaign report#
AcelleMail tracks every send attempt — including bounces — in the campaign's Tracking log. Open any sent campaign → Bounces tab:
Each row shows:
- Recipient email — who didn't receive
- Bounce type — Hard (permanent — invalid address, domain doesn't exist) or Soft (temporary — mailbox full, server unreachable)
- DSN reason — the receiving server's response, in plain-ish English
- Time — when AcelleMail tried to deliver
What AcelleMail does automatically#
You don't need to manually clean up most bounces. AcelleMail's bounce handling runs automatically:
- Hard bounces are marked as
unsubscribed after the first occurrence. They're removed from future sends to the same list. No action needed.
- Soft bounces are retried with backoff (next campaign batch). After 5 consecutive soft bounces, AcelleMail auto-promotes to hard bounce (treats as permanent).
- Spam complaints (recipient hit "This is spam") flow through SMTP-vendor webhooks (SES, SendGrid, Mailgun, Postmark) and immediately unsubscribe the subscriber.
The campaign overview shows the totals:
If Failed is <5% of the list, you're fine — that's the industry-typical churn from invalid + abandoned addresses on any list. If Failed is >10%, something needs attention (see "When to take action" below).
When to take action — UI-driven decisions#
| What you see in the log |
What it means |
What to do |
| Most bounces say "User unknown" / "Mailbox does not exist" |
Stale list — addresses that no longer exist |
Normal at <5%. Above that, run Subscribers → Email verification before next send. |
| Most bounces say "Mailbox full" / "Quota exceeded" |
Temporary issue on the recipient side |
Wait — AcelleMail retries automatically. No action. |
| Bounces concentrate on ONE recipient domain (e.g. all @example.com fail) |
The receiving server may be blocking your sending IP |
Check Settings → Sending servers for the IP being used. If multiple domains block you, IP reputation issue. See Why are my emails going to spam folder. |
| Bounces say "Authentication failed" / "DMARC failure" |
Your domain authentication (SPF / DKIM / DMARC) isn't configured correctly |
Run Settings → Domains → Verify and follow the wizard. |
| Bounces growing during a send (started low, spiking) |
Your sending IP is being rate-limited mid-send |
Sending server warm-up is incomplete OR daily quota exceeded. Wait or split campaign. |
The Subscribers view — clean up manually if needed#
If you want to manually mark certain addresses unsubscribed (e.g. an entire former-customer list), open Subscribers in a list, filter by status, and bulk-change:
- Filter by status
Failed to see hard-bounced addresses.
- Bulk-select rows → top toolbar → Change status → Unsubscribed.
- The list count + future sends update immediately; no separate suppression step needed.
Common UI signals — quick recap#
- Failed count <5% of list → ignore, AcelleMail handles it
- Failed count >10% of list → run email verification before next send
- Bounces clustered on one domain → IP/DNS issue, check sending server
- "Authentication failed" bounces → fix SPF/DKIM/DMARC
Advanced: SMTP DSN code reference for operators
SMTP responses follow RFC 3463 (Enhanced Mail System Status Codes). Three digits, separated by dots: X.Y.Z.
Class (X) — severity:
2.X.X — Success (delivered)4.X.X — Persistent transient failure (will retry — soft bounce)5.X.X — Permanent failure (will NOT retry — hard bounce)
Subject (Y) — what failed:
X.1.X — Addressing status (recipient address)X.2.X — Mailbox status (full, disabled, doesn't exist)X.3.X — Mail system status (overloaded, down)X.4.X — Network and routing statusX.5.X — Mail delivery protocol statusX.6.X — Message content or media statusX.7.X — Security or policy status (authentication, blacklist, DMARC)
Common codes you'll see:
| Code |
Meaning |
Action |
2.0.0 |
Message accepted for delivery |
Success — no bounce |
4.2.2 |
Mailbox full |
Soft — retried automatically |
4.7.0 |
General temporary failure (often greylisting) |
Soft — retried |
5.1.1 |
User unknown (recipient address doesn't exist) |
Hard — auto-unsubscribe |
5.1.2 |
Domain doesn't exist |
Hard — auto-unsubscribe |
5.2.0 |
Mailbox issue (suspended, archived) |
Hard |
5.2.1 |
Mailbox disabled |
Hard |
5.7.1 |
Delivery not authorized (blocked) — common when sender on blocklist |
Hard — investigate IP reputation |
5.7.26 |
DMARC failure (alignment policy) |
Hard — fix DKIM/SPF setup |
Reading the full DSN in the log:
The "DSN reason" column shows the full response string from the receiving server, e.g.:
550 5.1.1 <bob@example.com>: Recipient address rejected: User unknown in local recipient table
550 — SMTP-level rejection code (matches 5.X.X class)5.1.1 — Enhanced status code (RFC 3463)- The text after — server's human-readable reason
Querying the bounce log from the database for offline analysis:
php artisan tinker --execute='
\App\Model\BounceLog::where("campaign_id", <id>)
->where("dsn_status", "like", "5.7%")
->select("recipient", "dsn_status", "diagnostic_code")
->get()
->each(fn($r) => print("{$r->recipient}\t{$r->dsn_status}\t{$r->diagnostic_code}\n"));
'
Filtering FBL (Feedback Loop) entries — recipient marked your message as spam:
php artisan tinker --execute='
\App\Model\FeedbackLog::orderByDesc("created_at")
->limit(50)->get()
->each(fn($r) => print("{$r->recipient}\t{$r->feedback_type}\t{$r->created_at}\n"));
'
When the FBL volume rises sharply, your IP reputation is in jeopardy — pause campaigns to that segment, investigate content + frequency.
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