Invoices are landing in spam. Here is the eight-week fix.
A 35-person B2B software company runs cold email from its main domain. Then customers stop receiving invoices and support replies.
A representative example drawn from our hands-on experience. Company details are composite, and the figures are typical of this kind of project rather than from one named client.
The problem
Cold email from the main domain, a bought list and broken email authentication. Spam complaints run at twice the limit Gmail sets, and invoices start going to spam.
What we do
Stop cold email on the main domain the same day, fix SPF, DKIM and DMARC, and move outreach to secondary domains the company owns.
What changes
Customer email reaches the inbox again. Outreach restarts on its own domains and never touches the main one.
What we find, and what we change.
| Check | Before | After |
|---|---|---|
| SPF (fails past 10 lookups) | 13 lookups, failing | 7 lookups, passing |
| DKIM | Set up for one tool only | Every tool that sends as the company |
| DMARC | Missing | Quarantine policy, with reports |
| Cold email sent from | Main domain | 6 secondary domains |
| Email list | Bought, 11% bounce | Verified, under 2% bounce |
| Unsubscribe | None | One-click link in every email |
SPF, DKIM and DMARC are the three records that prove an email really comes from your company.
Spam complaints fall under the limit by week three.
Share of recipients marking the company's email as spam, week by week.
Representative figures. The 0.3% limit is the spam rate Gmail asks bulk senders to stay under.
How the outreach setup is built
Outreach gets its own domains, so a problem there can never reach customer email.
3 of 6 secondary domains shown, 3 mailboxes each.
| Mailbox | Sent today | Status |
|---|---|---|
| anna@getyourcompany.com | 28 / 30 | HEALTHY |
| mark@tryyourcompany.com | 30 / 30 | HEALTHY |
| sara@yourcompany.co | 12 / 30 | WARMING |
| leo@yourcompanyhq.com | 0 / 30 | PAUSED |
A paused mailbox is pulled out automatically and the rest keep sending.
Each mailbox sends what one person could send by hand. To send more, add domains and mailboxes, never more per mailbox. 50 mailboxes across 17 domains carries 1,500 a day.
How it works.
- 1
Day 1: stop the damage
Pause all cold email from the main domain and remove the bought list. Nothing else helps until this is done.
- 2
Week 1: fix authentication
Cut SPF from 13 lookups to 7, turn on DKIM for every tool that sends as the company, and add DMARC with reports.
- 3
Weeks 1 to 3: move outreach out
Set up 6 secondary domains with 18 mailboxes, split between Google Workspace and Microsoft 365, and warm them for three weeks.
- 4
Weeks 2 to 8: rebuild trust
Only real email from the main domain: invoices, support, replies. DMARC moves to quarantine in week 6.
- 5
Week 4 on: restart outreach, capped
30 emails per mailbox per day, every address verified first, and an unsubscribe link in every email.
- 6
Ongoing: monitor
Weekly inbox placement tests, plus the spam rate and compliance dashboards in Google Postmaster Tools. Weak mailboxes are pulled out.
The change in numbers.
| Metric | Before | After 90 days |
|---|---|---|
| Emails reaching the inbox | 38% | 96% |
| Spam complaint rate | 0.6% | 0.04% |
| Bounce rate | 11% | under 2% |
| Cold email from the main domain | all of it | none |
| Outreach meetings per month | 0 (paused) | 14 |
Representative figures.
Where this goes wrong
Hoping for four weeks. Mailbox providers rebuild trust slowly, so plan for eight. Stopping cold email fast matters more than any technical fix.
Warming new mailboxes too quickly. Placement dips, and the answer is to slow down and add a week.
Who this is for
Companies whose customers say "I never got your email".
Teams who want to start or scale cold email without putting the main domain at risk.
Common questions.
It can, if it is sent from that domain. In this setup none is. The main domain carries only customer and business email.
Domains you own that sit close to your brand name and are used only for outreach. Each one redirects to your main website.
The rules differ by country. Every email names the sender, carries an unsubscribe link, and opt-outs are honoured. We recommend checking the requirements for your markets, such as GDPR and CAN-SPAM, with a legal adviser.
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