Inbox Protection is a warm-up and reputation maintenance feature available in Hunter as a All in one outreach paid add-on.
It progressively builds your sender reputation by automatically sending emails and generating real replies, then continues to protect that reputation over time.
👉 Inbox Protection is available as a monthly and yearly subscription for email accounts connected to Email Sequences linked to All in one outreach paid plans.
Looking to gradually increase your sending volume in Sequences without warm-up? See Progressive Sending.
Inbox Protection builds your actual sender reputation through real email engagement, Progressive Sending only controls volume pacing.
⚠️ Important: Inbox Protection significantly improves your deliverability, but it cannot guarantee 100% inbox placement. To get the best results:
Wait until the initial warm-up phase is fully completed (minimum 30 days) before sending outreach emails from that account
Follow cold email best practices — send relevant, personalized content to verified recipients. No amount of warm-up will protect an account that sends spam or irrelevant bulk emails
Monitor your sending reputation using the Global Health dashboard and adjust your approach if issues arise
Inbox Protection gives your account the best possible foundation, but long-term deliverability depends on the quality of your outreach. See our Cold Email Guide for best practices.
What Inbox Protection does
When you enable Inbox Protection on an email account, Hunter will:
Automatically send warm-up emails from your account to a private network of real inboxes
Generate real replies to those emails, creating positive engagement signals
Sending volume starts low and progressively increases over the 30-day warm-up period, reaching approximately 30–40 emails per day with a 30% reply rate.
Track your warm-up progress, including interactions, open rates, reply rates, and spam placement
Automatically transition into maintenance mode after the warm-up phase to continuously protect your reputation
Why warm-up matters
Email providers like Gmail and Outlook constantly evaluate your sending behavior. A new or inactive email account has no established reputation, which means:
Your emails are more likely to land in spam
Recipient servers may block you outright
Even well-written, relevant emails can be filtered
Warm-up solves this by creating a history of positive engagement (sends, opens, replies) before you start your outreach. This tells email providers your account is legitimate and trustworthy.
Inbox Protection vs Progressive Sending
These are two different features that serve different purposes:
| Inbox Protection | Progressive Sending |
What it does | Builds and maintains sender reputation through real email engagement | Controls how fast your daily sending limit increases in Sequences |
How it works | Sends warm-up emails with real replies to a private inbox network | Gradually increases your daily sending cap over time |
Ongoing protection | Yes - continues in maintenance mode after warm-up | No - completes when target limit is reached |
Subscription | Paid add-on (monthly/yearly billing) | Included in all plans |
Can be used together? | No - when Inbox Protection is active, Progressive Sending is automatically hidden | No - when Inbox Protection is active, Progressive Sending is automatically hidden |
Who should use Inbox Protection
Inbox Protection is recommended for:
New email accounts that have never sent outreach before
Inactive accounts that haven't been used for sending in 30+ days
Accounts with deliverability issues where emails are landing in spam
Anyone scaling outbound who wants ongoing reputation protection alongside their sequences
Before you start
Don't send outreach emails from this account during warm-up. The warm-up process needs to be the primary activity on the account to be effective. Sending your own sequences during this period can compromise the results.
The warm-up period is of 30 days. This is the recommended duration to fully build your sender reputation. Shorter periods may not produce reliable results.
You may see warm-up emails in your inbox. These are automated emails sent as part of the warm-up process. They are identified internally and are normal — your account has not been compromised. You can identify them by searching for WBX in your inbox subject line.
How to enable Inbox Protection
Step 1: Open your email account profile
Go to the Email Account Center and click View on the email account you want to protect.
Step 2: Enable Inbox Protection
Navigate to the Inbox Protection tab in the account profile.
Click Enable Inbox Protection.
An OAuth authorization may be required (for Google and Outlook accounts) to allow the warm-up system to send emails on your behalf. Follow the prompts to complete authorization.
Choose the billing
Confirm your subscription.
Once enabled, the warm-up begins automatically. Hunter progressively increases the volume of warm-up emails sent from your account, starting low and building up to approximately 30-40 emails per day with a 30% reply rate.
Step 3: Monitor your progress
Once active, the Inbox Protection tab shows:
Warm-up status (warming up / protection active)
Daily interactions — emails sent and replies received
Open rates and reply rates
Spam rate — the percentage of warm-up emails landing in spam
What happens after warm-up completes
After the initial warm-up period (30 days), Inbox Protection does not stop. It automatically transitions into maintenance mode, continuing to send a controlled volume of emails and replies to keep your reputation healthy.
This is important because sender reputation is not permanent — it's constantly re-evaluated by email providers. If your sending activity fluctuates or you have a bad day where recipients mark your emails as spam, the ongoing warm-up activity helps offset the damage.
We recommend keeping Inbox Protection active for as long as you're using the account for outreach.
Sending limitations during warm-up
While Inbox Protection is actively warming up your account:
Your account is temporarily locked from sending in Sequences. This ensures the warm-up is the primary activity on the account.
You can unlock sending and set a custom daily limit if needed, but we strongly discourage sending a high volume during this period.
Email accounts in warm-up status will appear greyed out in the sequence creation flow to prevent accidental selection.
Once warm-up completes and the account moves to "Protection Active" status, you can use it normally in Sequences.
Subscription and billing
While Inbox Protection is actively warming up your account:
Your daily sending limit is set to 0 and sending is locked. This ensures the warm-up is the primary activity on the account and protects your deliverability.
Email accounts in warm-up status will appear greyed out in the sequence creation flow to prevent accidental selection.
Unlocking sending during warm-up
If you need to send emails before the warm-up is complete, you can click Unlock sending in the email account profile tab under the daily sending limit section.
Before unlocking, Hunter will warn you:
"This email account is still warming up. Sending early can affect deliverability. If you continue, daily sending limits will stay low during warm-up."
⚠️ We strongly recommend against unlocking sending during the warm-up period. Sending your own emails while the account is warming up can compromise the warm-up results and hurt your deliverability. If possible, wait until the warm-up is fully completed before starting your sequences.
Once warm-up completes and the account moves to "Protection Active" status, sending is automatically unlocked and you can use the account normally in Sequences.
How to cancel Inbox Protection
You can cancel the Inbox Protection renewal from the Subscription section of your Hunter account. When you cancel:
Inbox Protection remains active until the end of your current prepaid period (monthly or yearly) — it is not disabled immediately
After the prepaid period ends, protection stops and the account moves to a "Limited" status
The account profile will show when the account was last warmed up and the date protection ended
You can re-enable Inbox Protection at any time from the Inbox Protection tab in the email account profile. If re-enabled, the warm-up process starts fresh.
⚠️ Inbox Protection subscriptions are tied to a specific email account and cannot be transferred to a different account. If you want to protect a different email account, you'll need to purchase a separate Inbox Protection subscription for it.
Managing warm-up emails in your inbox
During warm-up, you may notice emails with unfamiliar content appearing in your inbox. This is completely normal — these are automated warm-up emails sent as part of the process, and your account has not been compromised.
You can identify them by searching for WBX in your inbox subject line. To keep your inbox tidy, we recommend setting up a filter to automatically route these emails to a dedicated folder.
Gmail / Google Workspace
In Gmail, click the Settings icon and select See all settings.
Go to the "Filters and Blocked Addresses" tab and click Create a new filter.
In the "Subject" field, type
WBXand click Create filter.
Select the following options:
Skip the Inbox (Archive it)
Apply the label — choose an existing label or create a new one (e.g. "Warm-up emails")
Also apply filter to matching conversations
Click Create filter to save.
Warm-up emails will now be automatically moved to your chosen label and skip your main inbox. You can still access them at any time from the label in the left sidebar.
Outlook / Microsoft 365
In Outlook, go to Settings and select View all Outlook settings.
Navigate to Mail > Rules and click Add new rule.
Name the rule (e.g. "Warm-up emails").
Under Add a condition, select Subject includes and enter
WBX.Under Add an action, select Move to and choose or create a folder (e.g. "Warm-up emails").
Click Save.
Warm-up emails will now be automatically moved to your chosen folder and won't clutter your main inbox.
Common questions
Can I use Inbox Protection and Progressive Sending at the same time? No. Inbox Protection includes progressive volume increases as part of the warm-up process, so Progressive Sending is automatically hidden when Inbox Protection is active.
Will I see warm-up emails in my inbox? Yes — you may notice emails with unfamiliar content in your inbox. These are part of the warm-up process and are normal. They can be identified by searching for "WBX" in the subject line. See the Managing warm-up emails in your inbox section above to set up a filter.
How long should I keep Inbox Protection active? We recommend keeping it active for as long as you use the account for outreach. Sender reputation is dynamic and needs continuous maintenance.
Can I send my own sequences during warm-up? We strongly discourage it. During the initial warm-up period (minimum 30 days), the warm-up process should be the primary activity on the account. After warm-up completes and the status changes to "Protection Active," you can send normally.
What happens if I cancel Inbox Protection? Protection stays active until the end of your current billing period. After that, the account moves to "Limited" status — it may still perform well for a while, but reputation can weaken over time without continued maintenance. The account profile will show when it was last warmed up so you can track this.
Can I re-enable Inbox Protection after cancelling? Yes. Go to the Inbox Protection tab in the email account profile and click Enable inbox protection. The warm-up process will start from scratch.
Can I transfer Inbox Protection to a different email account? No. Inbox Protection is specific to the email account it was purchased for and cannot be moved to another account. You'll need to purchase a separate subscription for each account you want to protect.
Does Inbox Protection work with all email providers? It works with Gmail, Google Workspace, Outlook, Microsoft 365, and SMTP/IMAP accounts connected to Email Sequences. Google and Outlook accounts require an additional OAuth authorization step.