A damaged IP reputation — whether from a single bad campaign, a compromised account, or accumulated poor sending practices — is not necessarily permanent. With the right approach, most senders can recover within weeks to months. This article explains how to identify the extent of the damage, take the correct remediation steps, and prevent recurrence.
Signs That Your IP Reputation Is Damaged
| Symptom | Likely Cause |
|---|---|
| Delivery rate suddenly dropped below 85% | IP or domain has been flagged or blacklisted by major ISPs |
| Gmail delivery specifically failing while others are OK | Domain or IP reputation dropped to Low/Bad in Google Postmaster Tools |
| Outlook users reporting non-delivery | Listed on Microsoft's blocklist or Spamhaus XBL/PBL |
| Transactional emails not arriving (OTPs, password resets) | Reputation problem affecting all email types from this IP/domain — critical situation |
| SMTP 550/5xx rejection responses from receiving servers | Hard block — receiving server is actively rejecting your IP |
| Sender Score below 50 | Aggregate reputation data showing serious historic sending problems |
Step 1 — Stop and Assess
Immediately stop sending until you understand the cause. Continuing to send while your reputation is damaged compounds the problem — every additional rejected email or spam complaint makes recovery harder and longer.
- Run a full blacklist check at MXToolbox (mxtoolbox.com/blacklists.aspx) on your sending IP.
- Check Google Postmaster Tools for domain reputation and spam rate data.
- Check Sender Score at senderscore.org.
- Review your MigoSMTP Delivery Reports for the last 7 days — look for spikes in complaints, bounces, or deferral rates that correlate with when the problem started.
- Identify the specific campaign or time period when metrics deteriorated.
Step 2 — Identify and Fix the Root Cause
| Root Cause | Fix Required |
|---|---|
| High complaint rate from a bad campaign | Identify the problematic segment; remove them from all future sends; review consent documentation for that segment; improve unsubscribe visibility |
| High bounce rate — poor list quality | Remove all hard bounces; run remaining list through an email verification service; implement double opt-in going forward |
| Spam trap hits | Indicates purchased or harvested list, or sending to very old addresses — purge any list not built through organic opt-in; never use a purchased list again |
| Account compromise — unauthorised sending | Reset all SMTP and API credentials immediately; review delivery logs for unauthorised sends; report to Rackwave support; contact affected ISPs |
| Authentication failures | Verify SPF, DKIM, and DMARC records are correctly published and passing; check for recently changed DNS that may have broken records |
| Volume spike without warmup | Commit to a proper warmup schedule going forward; do not send large batches all at once |
Step 3 — Request Delisting (Where Applicable)
If you are listed on specific blacklists, submit removal requests after fixing the root cause — most blacklists will not remove you until the underlying issue is resolved:
| Blacklist | Delisting URL | Typical Wait Time |
|---|---|---|
| Spamhaus SBL | spamhaus.org/lookup/sbl/ | 24–72 hours after investigation |
| Barracuda BRBL | barracudacentral.org/rbl/removal-request | 24–48 hours typically |
| Microsoft Outlook | sendersupport.outlook.com/pm/troubleshooting.aspx | 24–72 hours |
| Google (Postmaster) | Google does not have a manual delisting — reputation recovers as positive signals accumulate | 2–4 weeks of clean sending |
Step 4 — Rebuild With a Recovery Sending Plan
After fixing the root cause and submitting any necessary delisting requests, begin sending again — but treat your IP as if it were new:
- Start with very low volume — 50–100 emails per day maximum in the first week.
- Send only to your most engaged recipients — people who have opened your emails in the last 14 days.
- Follow the full warmup schedule — exactly as you would for a brand new IP.
- Monitor daily — check Postmaster Tools and Sender Score every day; any regression means pausing again.
- Do not rush the volume ramp-up — adding volume before reputation is restored will undo recovery progress.
Recovery Timeline Expectations
| Damage Level | Typical Recovery Time | Notes |
|---|---|---|
| Minor — one bad campaign, Sender Score dipped to 60–75 | 2–4 weeks of clean sending | Reputation buffer from existing history helps; faster recovery |
| Moderate — multiple bad campaigns, listed on minor blacklists | 4–8 weeks | After delisting; requires full warmup restart |
| Severe — Spamhaus listing, Google reputation Bad | 2–4 months | May require dedicated IP migration; domain may need to be replaced if domain reputation is also severely damaged |