Settings
Threads
Concurrent connections for checking. Up to 2,000 with a Mail subscription.
Higher threads = faster checking, but more proxy bandwidth and a higher chance of triggering rate limits on some providers. Start at 50–100 and increase gradually.
Timeout
Connection timeout per check. Default: 30 seconds. Increase for slow networks.
Retries
Retry attempts for transient errors. Default: 2.
Only transient errors are retried: connection failures, timeouts, proxy errors, TLS errors. Permanent results (invalid login, 2FA, locked) are never retried.
Protocols
| Protocol | Plan | Notes |
|---|---|---|
| IMAP | All | Primary protocol for most providers |
| POP3 | All | Fallback when IMAP unavailable |
| SMTP | All | Validates sending capability |
| Outlook | Pro | Microsoft consumer domains (hotmail, outlook, live, msn) |
| Outlook Corp | Pro | Microsoft 365 corporate accounts — auto-detected by MX record |
| ABV | Pro | abv.bg, gbg.bg, gyuvetch.bg |
| GMX | Pro | gmx.com, gmx.net, gmx.de, web.de |
Microsoft consumer domains are automatically routed to Outlook when enabled. Corporate M365 accounts (any domain whose MX points to Microsoft 365) are auto-detected and authenticated via Azure AD — no manual configuration required. GoDaddy, Zoho, FastMail, and other hosted IMAP providers are also auto-discovered.
Proxies
Load proxy lists from the Results tab. Types: HTTP CONNECT, SOCKS4, SOCKS5 — all available on all plans.
Each thread uses one proxy connection. Aim for at least as many proxies as threads (2–3x is ideal). Krantz Mail rotates through the list and skips failed proxies temporarily.
Search
Add search queries to run automatically on successful validations. Types: Body, Subject, From, To. Results are saved alongside the output.
Presets
Save and load named settings configurations. Presets are synced to your account and available across devices.
Display
- Auto-scroll — table scrolls as new results arrive
- Notifications — sound and desktop alerts on completion