Spot the gatekeepers before you send
Sendbox checks whether a recipient's domain sits behind a Secure Email Gateway. Once flagged, you choose: skip that lead entirely, or route them through specific mailboxes set aside for SEG handling.
Lambda Group
Campaigns
Campaign | Status | Leads | Sent | Opened | Replied | Positive | Bounced | |
|---|---|---|---|---|---|---|---|---|
SaaS VP Decision Makers | Active | 4,200 | 2,847 | 1,748(61.4%) | 236(8.3%) | 92(39.0%) | 51(1.8%) | |
Series A Founders – West Coast | Active | 1,800 | 1,204 | 784(65.1%) | 133(11.0%) | 61(45.9%) | 19(1.6%) | |
Agency Owners Outreach | Paused | 5,600 | 3,891 | 2,218(57.0%) | 214(5.5%) | 72(33.6%) | 82(2.1%) | |
Enterprise IT Directors | Completed | 7,100 | 5,102 | 3,265(64.0%) | 453(8.9%) | 176(38.8%) | 92(1.8%) | |
RevOps Teams Q1 2025 | Draft | 920 | - | - | - | - | - |
Sidestep spam filters before you hit send
Sendbox spots Secure Email Gateways before you send, so you're never going in blind.
Exclude SEG-protected leads from a campaign automatically if you'd rather not deal with the deliverability risk.
Send SEG-protected domains through mailboxes you've designated, with different sending patterns.
Handling SEG leads separately keeps your overall campaign numbers accurate.
Catch the risk before it costs you a send
Before anything sends, Sendbox checks whether the recipient's domain sits behind a Secure Email Gateway.
Two options: skip SEG-protected leads automatically, or route them through mailboxes you've designated for that kind of handling.
SEG-protected domains are tougher to land in. Catching them upfront avoids wasted sends and keeps your deliverability numbers clean.
Enterprise domains often sit behind a SEG. Catch that upfront and decide whether to skip the lead or route it through a mailbox built for the job.
SEG-protected domains tend to bounce and spam-flag more often. Skipping or isolating them keeps your overall metrics honest.
Send SEG-protected domains through mailboxes with warmer reputations or different sending patterns to improve your odds.
Caught upfront, not diagnosed after the fact
Know about a SEG before you send, not after
Most cold email tools send blind and leave you to figure out why deliverability tanked. Sendbox flags Secure Email Gateways on recipient domains upfront, so you can skip those leads or route them through specific mailboxes instead.
Skip it or route it — your call
Once a SEG is detected on a recipient's domain, you get two options: skip the lead entirely, so they receive nothing from that campaign, or route them through mailboxes you've set aside for SEG handling.
Got questions? We've got answers.
Still stuck? Talk to us →Sendbox flags when a recipient's domain is protected by a Secure Email Gateway, so you can skip those leads or route them through specific mailboxes.
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