Why a prospect was automatically marked as bounced

The short version

If a prospect in your campaign shows the status Bounced, it means WarmySender detected that an email to that address could not be delivered, and stopped sending to it for you. This is a good thing: it keeps you from repeatedly emailing an address that doesn't work, which is one of the fastest ways to damage your sender reputation and hurt your deliverability for everyone else on your list.

WarmySender is a 4-pillar outreach platform — Cold Emailing, Email Warmup, LinkedIn Outreach, and Multichannel sequences. This page is part of the cold emailing pillar: how WarmySender protects your reputation by handling bad addresses automatically.

What "bounced" actually means

A bounce is when an email you sent can't be delivered to the recipient's mailbox. The most common reasons are that the address doesn't exist (a typo, or a person who has left the company), the mailbox is full, or the receiving mail system refused the message. When that happens, a delivery-failure notice is generated to say the email didn't get through — the email equivalent of a returned letter stamped "no such address."

WarmySender reads those delivery-failure notices for you and marks the matching prospect as Bounced so you don't have to watch your inbox for them or guess which addresses are bad.

Two kinds of bounce we catch

Delivery failures don't always arrive the same way. WarmySender catches both kinds automatically:

1. Immediate rejections at send time

Sometimes the receiving mail system rejects the email the moment you try to send it — for example, when the address clearly doesn't exist. WarmySender sees the rejection right away, marks the prospect as Bounced, and moves on. There's no waiting and nothing for you to do.

2. Delayed "delivery failure" notices that arrive later

Other times the email is accepted first, and a delivery failure notice arrives in your sending inbox a little later — minutes or sometimes hours afterward — to say the message ultimately couldn't be delivered. WarmySender watches your sending inbox for these notices, matches each one back to the right campaign and prospect, and marks that prospect as Bounced too. This is the part that's easy to miss by hand, because the failure shows up after the send looked like it went fine — so WarmySender handles it for you.

Where to see the bounced status

Open the campaign, then go to the Prospects tab. Each prospect shows a status, and bounced addresses are clearly marked Bounced. You can filter the list by status to see all of your bounced prospects in one place, which is handy when you want to review or clean up your source list. The campaign's overall stats also reflect bounces so you can keep an eye on the bounce rate for the campaign as a whole.

Bounced prospects are excluded from future sends

Once a prospect is marked Bounced, WarmySender automatically stops sending to that address — both for the remaining steps of the current campaign and for future sends. You won't keep hitting a known-bad address again and again. This is the protective part: every repeated send to an invalid address chips away at your sender reputation, so removing those addresses from the rotation keeps your good emails landing in inboxes.

A worked example

You launch a 3-step cold email campaign to 300 prospects. One of them, [email protected], left that company months ago and the address no longer exists.

• For most of your list, step 1 sends normally.
• For [email protected], a delivery-failure notice comes back shortly after step 1 goes out, saying the address can't be reached. WarmySender catches that notice and marks Jordan as Bounced.
• When you open the campaign's Prospects tab, Jordan shows the Bounced status. You filter by Bounced and see exactly which addresses on your list are dead.
• Steps 2 and 3 are not sent to Jordan — the address is excluded automatically — so you don't waste three more sends pounding an invalid mailbox and dragging down your reputation. Your other 299 prospects continue through the sequence as normal.

Why this protects you

High bounce rates are one of the strongest signals that mailbox providers use to decide whether your emails belong in the inbox or in spam. By detecting delivery failures automatically and excluding those addresses, WarmySender keeps your bounce rate low without you having to babysit your inbox. Account safety and deliverability always win: it's better to quietly drop a bad address than to keep emailing it and risk your sender reputation for the whole campaign.

The best long-term habit is to start with clean, verified lists so there are fewer bad addresses to begin with. Automatic bounce handling is your safety net for the ones that slip through — people who changed jobs, typos in an import, or addresses that simply went dead since you collected them.

Common questions

A prospect shows Bounced but I think the address is valid. What happened?

WarmySender marks a prospect Bounced when it receives a delivery-failure notice for that address. Occasionally a mailbox can return a temporary failure (for example, a full inbox or a brief problem on the receiving side). If you're confident the address is correct, double-check it for typos, and reach out to [email protected] with the campaign name and the address — we'll take a look at exactly what came back.

Does a bounce stop the whole campaign?

No. A bounce only affects that one prospect. The rest of your list keeps moving through the sequence normally. Only the bounced address is excluded from further sends.

Will WarmySender keep emailing a bounced address?

No. Once an address is marked Bounced, it's automatically excluded from the remaining steps of that campaign and from future sends. That's the whole point — you stop wasting sends on addresses that don't work and you protect your reputation.

Why was a prospect marked bounced hours after I sent the email?

Some delivery failures aren't reported instantly. The receiving system may accept the email first and then send a delivery-failure notice back to your inbox a little later. WarmySender watches for those delayed notices and updates the prospect's status when one arrives — so a bounce can appear some time after the original send.

Where do I see all my bounced prospects?

Open the campaign, go to the Prospects tab, and filter by the Bounced status. That shows every bounced address for the campaign in one list, which makes it easy to review and clean up your source data.

Does this apply to email warmup too?

Automatic bounce detection described here is about your cold email campaigns — the messages you send to real prospects. Email warmup is a separate system that builds your sender reputation in the background and manages its own network behind the scenes. If you're trying to understand why a campaign prospect was excluded, the Prospects tab status is the place to look.

Related guides

• Why was this prospect skipped (bounce)? — More on how skipped and bounced prospects are handled
• See which recipients opened your emails — Track engagement on the prospects who did receive your email
• Setting up your first campaign — Start with a clean list and a solid sequence
• Bulk import mailboxes — Connect and configure your sending mailboxes
• Full documentation — All guides
• Support — How to get in touch