A contact who didn't get your campaign is almost always suppressed — Groupmail deliberately skipped them to protect your sending reputation. Suppression is automatic, and it happens for a small number of specific reasons.
Why is a contact suppressed?
A contact is skipped for one of these reasons:
- It hard bounced. The receiving server said the address doesn't exist. Sending again damages your reputation, so we stop.
- They marked a message as spam. A complaint is the strongest possible signal not to send again.
- The send was dropped before delivery.
- They unsubscribed — from the footer link, or by replying to ask.
The first three and the last work differently, and it's worth knowing which is which.
Hard bounces, complaints and dropped sends go to your account's exclusion list. Once an address is there, every future campaign skips it — including campaigns to a different group. Those are deliverability problems, so they apply account-wide to protect your sending domain.
An unsubscribe is different. It's recorded against the contact in the group they opted out of, and it doesn't affect your other groups. That's intentional: leaving one list shouldn't cancel the others they still want.
What's the difference between a hard and a soft bounce?
Groupmail reads the delivery report the receiving mail server sends back and parses its status code and diagnostic message.
- Hard bounce — permanent. The mailbox doesn't exist, or the domain doesn't accept mail. The address is suppressed.
- Soft bounce — temporary. A full mailbox, a server that's briefly down, or greylisting. These aren't suppressed; the address stays active for future sends.
Replies to your campaigns are also read and sorted. A genuine reply from a human is routed to your group Inbox; an out-of-office auto-reply is recognised and ignored rather than treated as a bounce.
Suppression isn't a punishment for the contact — it's a guard on your ability to reach everyone else.
Why was a contact flagged when I imported it?
New contacts are checked automatically, and one that fails is flagged rather than silently dropped. There are three flag types:
- Invalid — the address can't receive mail at all: the domain has no MX records, or the address isn't validly formed.
- Junk — a disposable or temporary-mailbox service, the kind used to get past a signup form once.
- Spam — the address appears in spam databases, or shows the submission patterns of a bot rather than a person.
Can my whole account be paused?
Yes — automatically, if sending health gets bad enough. Groupmail checks recent sending and acts at two levels. Both only apply once you've sent at least 100 emails in the window, so a small test send can't trigger either.
Flagged for review — at a hard bounce rate above 5% or a complaint rate above 0.3%. Sending continues; the account is marked for a human to look at.
Locked automatically — at a hard bounce rate above 15% or a complaint rate above 1%. Running campaigns are cancelled and further sending stops until the account is reviewed. You'll get an email explaining which threshold was crossed.
For context, a healthy list typically bounces well under 2% and draws complaints in the hundredths of a percent. Crossing these lines usually means a list is old, bought, or was imported without permission.
How do I fix it?
- Stop sending to the affected list until you understand why it's bouncing.
- Clean the list — remove addresses you can't account for, and anything that has already hard bounced.
- Check how the contacts were collected. Addresses gathered without clear consent are the usual cause of complaints.
- Contact support if your account has been locked. Locks are reviewed by a person, not lifted on a timer.
Quick answers
Why did one contact not receive my campaign? Either they're on your account's exclusion list after a hard bounce, complaint or dropped send — which applies to every group — or they unsubscribed from that particular group, which is recorded on the contact and affects only that group.
Does suppression apply to just one group? It depends which kind. Hard bounces, complaints and dropped sends apply across your whole account, because they protect your sending domain. An unsubscribe applies only to the group it happened in, so someone can leave one list and stay on another.
Will a soft bounce suppress a contact? No. Only hard bounces suppress. Soft bounces are temporary — a full mailbox or a server briefly unavailable — and the contact stays active.
What does an Invalid, Junk, or Spam flag mean? Invalid means the address can't receive mail at all. Junk means a disposable mailbox service. Spam means the address appears in spam databases or looks bot-submitted.
Can Groupmail lock my account automatically? Yes, once you've sent at least 100 emails in the window, if hard bounces exceed 15% or complaints exceed 1%. A lighter review flag triggers at 5% bounces or 0.3% complaints.