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 |
| Outlook Corp | Any domain with MX → Microsoft 365 (auto-detected) | Pro |
| ABV | abv.bg, gbg.bg, gyuvetch.bg | Pro |
| GMX | gmx.com, gmx.net, gmx.de, gmx.at, gmx.ch, web.de | Pro |
Outlook and Outlook Corp use Microsoft’s authentication APIs. Outlook handles consumer accounts (Hotmail/Outlook.com). Outlook Corp handles any corporate domain hosted on Microsoft 365 — detected automatically when the domain’s MX record points to *.mail.protection.outlook.com. GoDaddy, Zoho, FastMail, and other hosted IMAP providers are discovered via ISPDB lookup. ABV and GMX are provider-specific web protocols. All non-standard protocols fall back to IMAP if unavailable.
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.