The purpose
Email verification is a pre-send check.
Lists decay. People change jobs, mailboxes close, domains disappear and temporary addresses enter your database. Verification checks the evidence available now so you can identify clear problems and uncertain records before a campaign.
It is not an email sending service. It does not measure your sender reputation or decide whether message content will trigger a spam filter. It also does not prove that a future message will reach the inbox.
Think of the result as a point-in-time assessment: useful evidence for a decision, not a guarantee.
The checks
What VXSentry looks at.
- 01
Format
Checks the address structure before deeper work begins.
- 02
Domain and mail routing
Looks for the DNS records a domain needs to receive mail.
- 03
Mailbox response
Asks the receiving server about the recipient when its policy and the network permit it. The check stops before message content is sent.
- 04
Catch-all behavior
Tests whether a domain appears to accept arbitrary recipients, which makes one mailbox hard to confirm.
- 05
Disposable providers
Checks the domain against maintained temporary-email intelligence.
- 06
Role and pattern signals
Flags labels such as sales@ or support@ and other patterns that deserve caution.
- 07
Suppression intelligence
Checks applicable entries maintained for the account and platform. It does not remove contacts from an outside tool.
The output
How to read the six categories.
Looks good
The receiving server accepted the mailbox and the domain did not behave like a catch-all. It is a reasonable candidate for sending, not a delivery guarantee.
Recommended: Send
Leave it out
The address has invalid syntax, its domain cannot receive mail, or the receiving server rejected the mailbox.
Recommended: Suppress
Think twice
The address matched an applicable VXSentry or account suppression entry, or uses a known disposable provider.
Recommended: Do not send
Use caution
The address has a role-based label or another suspicious pattern that deserves review, even when other checks look healthy.
Recommended: Send with caution
Mailbox uncertain
The domain appears to accept arbitrary recipients, so its response cannot confirm that this individual mailbox exists.
Recommended: Verify manually
We won’t guess
The domain can receive mail, but the provider did not give enough information to confirm or reject this mailbox.
Recommended: Recheck later
What verification does
- — Finds malformed addresses and domains that cannot receive mail.
- — Records mailbox responses when the provider permits the check.
- — Separates catch-all behavior and honest uncertainty.
- — Adds clear result fields while preserving original CSV columns.
What verification does not do
- — Guarantee delivery, inbox placement or zero bounces.
- — Identify every possible spam trap.
- — Replace SPF, DKIM or DMARC for your sending domain.
- — Remove or sync contacts in your external sending platform.
Using the file
Filter with your own sending policy.
Download the enriched CSV, then decide how each category fits your risk tolerance. Leave clear Undeliverable results out. Treat High risk records conservatively. Review Risky and Catch-all records instead of reading them as confirmed mailboxes. Recheck Unknown records later when timing matters.
List decay
A clean list does not stay clean forever.
Need a specific answer? Visit the email verification FAQ.