If you’re running cold outbound email campaigns and your open rates have tanked, you might have a sender reputation problem. That’s a fancy way of saying inbox providers think you send spam. The good news? Tools like Mailivery make it a lot easier to see where you stand—and give you practical ways to fix things.
This guide is for founders, SDRs, and marketers who want their emails to hit inboxes, not get lost in the void. If you’re tired of guessing why your deliverability sucks, or you just want a straightforward way to keep your sender score healthy, read on.
What is “Sender Score” and Why Should You Care?
Sender score is a number (usually 0-100) that reflects how trustworthy mailbox providers (like Gmail or Outlook) think you are. A low score means your emails are more likely to go to spam, or get blocked entirely.
Some key things that tank your sender score: - Sending to bad or stale lists (bounces kill you) - High complaint rates (people marking you as spam) - Sudden spikes in volume - Poor engagement (nobody opens or replies)
It’s not just about the tech—it’s about trust. And if you’re running outbound, you need every edge you can get.
Step 1: Set Up Your Email Infrastructure (Don’t Skip This)
Before you touch Mailivery, make sure your sending setup isn’t shooting you in the foot. No tool can fix bad basics.
Minimum checklist: - Custom domain: Never blast cold emails from your main company domain. Use a dedicated sending domain/subdomain. - SPF, DKIM, DMARC: Authenticate your sending domain. If you don’t know what these mean, look them up and set them up before you go further. - Warm up new inboxes: Don’t go from zero to 500 emails a day. Ramp up slowly, or use a warm-up tool (Mailivery can help here).
Pro tip: If you’re using Google Workspace or Outlook, create separate inboxes for outbound. If they get burned, your main business emails stay safe.
Step 2: Connect Your Inbox to Mailivery
Once your basics are handled, it’s time to get Mailivery running.
Here’s what to do: 1. Sign up and log in to Mailivery. 2. Add your email account. Mailivery supports most major providers (Google, Outlook, SMTP). Use the OAuth or app password methods if available—way more secure than plain passwords. 3. Pick your plan. You don’t need all the bells and whistles—start small and scale if you see results.
What Mailivery actually does:
It sends and receives emails from your account to a network of real, monitored inboxes, simulating real conversations. If those emails land in spam, Mailivery moves them to the inbox and replies, helping train algorithms that you’re a “real” sender.
What to ignore:
Don’t obsess over every feature. Focus on connecting your sending account and letting the system run.
Step 3: Monitor Your Sender Score and Deliverability
Mailivery gives you dashboards and reports about your deliverability. Here’s how to make sense of them:
Key metrics to watch: - Inbox placement rate: What % of your emails land in the primary inbox vs. spam or promotions? - Sender score (or reputation): The higher, the better. Anything under 70 is a red flag. - Blacklist status: If you’re on a spam list, fix it ASAP.
How to use this info: - If your inbox placement is below 85%, slow your sending and check your content. - If your sender score is dropping, pause campaigns and focus on improving engagement. - If you’re blacklisted, stop sending and clean up your lists.
Don’t get distracted:
Open rates are unreliable (thanks, Apple privacy changes). Focus on reply rates and inbox placement instead.
Step 4: Use Mailivery’s “Warm-Up” to Build (or Rebuild) Reputation
Here’s where Mailivery earns its fee: the automated warm-up.
Why warm-up matters:
ISPs want to see natural, gradual email activity—not sudden blasts. Mailivery mimics this by sending and replying to small batches daily, making your account look legit.
How to set it up: - In Mailivery, enable the warm-up feature for your account. - Set the daily volume—start at 10-20 emails/day and increase by 5-10 every week. - Let it run for at least 2-4 weeks before launching a big outbound push.
Pro tip:
Don’t turn off warm-up once you start campaigns. Keeping it running in the background helps maintain your reputation, especially if you hit a rough patch.
What NOT to expect:
Warm-up isn’t magic. If your sending practices are bad (spammy content, bad lists), Mailivery won’t save you. It’s a supplement, not a fix-all.
Step 5: Act on What Mailivery Tells You
Mailivery gives you lots of feedback. Here’s how to actually use it:
- If you’re hitting spam:
- Cut your daily volume immediately.
- Check your email content for spammy phrases (free, guarantee, urgent, etc.)
- Remove unengaged contacts from your list.
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Keep the warm-up running—don’t panic and blast more emails.
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If your sender score recovers:
- Ramp up sending slowly—10-20% per week, not all at once.
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Keep monitoring. Sender reputation can tank quickly if you get lazy.
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If nothing improves after a month:
- Consider swapping to a new domain/inbox. Sometimes, it’s faster to start fresh.
Real talk:
Mailivery can tell you what’s wrong, but you have to fix the source—your list quality, your messaging, your cadence.
Step 6: Ongoing Maintenance (The Boring Part That Actually Works)
Maintaining sender score isn’t a one-and-done job. Keep these habits:
- Keep your lists clean. Remove bounces and unresponsive contacts regularly.
- Monitor deliverability weekly. Check Mailivery or similar reports at least once a week.
- Never send huge blasts out of the blue. Sudden spikes look suspicious.
- Rotate sending domains and inboxes. If you do serious outbound, spread the risk.
Pro tip:
If you’re running multiple inboxes, stagger your campaigns and warm-ups. Don’t put all your eggs in one sending basket.
What Works, What Doesn’t, and What to Ignore
What works: - Warming up new inboxes (via Mailivery or similar tools) - Regularly checking sender score and acting on problems early - Keeping lists fresh and targeted
What doesn’t: - Ignoring bounces and complaints - Sending huge volumes right away - Relying on “tricks” instead of genuine engagement
Ignore the hype: - Don’t believe anyone who says you can “guarantee” inboxing. Deliverability is always changing. - Don’t get distracted by vanity metrics. Open rates don’t mean much if your emails are in spam.
Keep It Simple and Keep Iterating
Here’s the bottom line: Mailivery is a solid tool for tracking and improving sender score, but it won’t fix deeper issues like bad lists or spammy tactics. Use it to monitor your reputation, automate your warm-up, and spot problems before they kill your campaign. But don’t overthink it—focus on sending good emails to people who actually want them, and build from there. If something’s not working, change it up and watch the numbers. Simple beats clever, every time.