Protocols & Status Codes
Protocol Selection
Krantz Mail selects the best protocol automatically. You don’t need to configure per-domain routing.
| Protocol | Domains | Plan |
|---|---|---|
| IMAP | All others (primary) | All |
| POP3 | All others (fallback) | All |
| SMTP | All (sending check) | All |
| Outlook | hotmail.*, outlook.*, live.*, msn.com | Pro |
| ABV | abv.bg, gbg.bg, gyuvetch.bg | Pro |
| GMX | gmx.com, gmx.net, gmx.de, gmx.at, gmx.ch, web.de | Pro |
Outlook, ABV, and GMX are webmail protocols — they connect through provider-specific web interfaces and may temporarily stop working if the provider changes their login flow. Affected domains fall back to IMAP automatically. IMAP, POP3, and SMTP are open standards and always available.
Status Codes
| Status | Meaning | Retried | Output File |
|---|---|---|---|
| Success | Valid login | — | success.txt |
| InvalidCredentials | Wrong password | No | invalid.txt |
| TwoFactorRequired | 2FA / MFA enabled | No | 2fa.txt |
| AccountLocked | Disabled or suspended | No | locked.txt |
| PasswordChangeRequired | Password expired | No | password_change.txt |
| RecoveryRequired | Identity verification needed | No | recovery.txt |
| CaptchaRequired | CAPTCHA challenge | No | captcha.txt |
| RateLimited | Too many attempts | Yes* | rate_limited.txt |
| ConnectionFailed | Can’t reach server | Yes | connection_failed.txt |
| Timeout | Timed out | Yes | timeout.txt |
| ProxyError | Proxy failed | Yes | proxy_error.txt |
| TlsError | SSL/TLS failure | Yes | tls_error.txt |
| TlsCipherError | Cipher suite unsupported | No | tls_cipher_error.txt |
| ProtocolError | Protocol-level error | No | protocol_error.txt |
| ProtocolMismatch | Protocol not supported | No | protocol_mismatch.txt |
| ServerNotFound | No mail server for domain | No | server_not_found.txt |
| Cancelled | Aborted mid-check | — | cancelled.txt |
| Unknown | Uncategorized failure | — | unknown.txt |
* RateLimited retries use backoff delays.