Smart | Scalable | Multi-threaded | Real-time | Accurate

Super Bulk Email Verifier is a powerful and intelligent desktop application designed to verify the validity, deliverability, and reputation of email addresses in bulk. It performs deep multi-layer validation — from syntax and DNS to live SMTP response and domain reputation — ensuring your email lists are clean, verified, and ready for marketing or CRM use.

• Syntax Validation: Detects invalid or malformed email formats.
• Domain & MX Lookup: Checks domain existence and MX mail server records.
• SMTP Live Verification: Directly connects to mail servers to confirm mailbox availability.
• Catch-All Detection: Identifies domains accepting all addresses (fake delivery).
• SPF / DMARC / DNS TXT Scan: Validates real sending authority and anti-spam policies.
• Relay & Forwarding Detection: Marks relay-only and redirection-based domains.

Generates a Trust Score using AI-based analysis of:

• MX quality and domain age
• SPF / DMARC / TXT record consistency
• Catch-All and relay detection
• Vendor reputation (Google, Outlook, Zoho, etc.)
• SMTP behavior patterns and reliability

Automatically ranks each email into High / Medium / Low Trust levels.

• Parallel verification with adjustable thread count (10–500).
• Adaptive timeout reduction for unstable or blocked ports.
• Dynamic MX prioritization (587 → 25 → 465) based on previous success rate.
• Automatic IPv4 / IPv6 fallback detection.
• Asynchronous DNS resolution for ultra-fast processing.

• Auto retry and fallback when primary MX fails.
• Smart network environment detection (alerts if SMTP outbound ports are blocked).
• Anti-block random delay injection to prevent server blacklisting.

• Interactive progress view with accurate percentage, speed, and ETA display.
• Non-flickering double-buffered UI updates.
• Pause / Resume / Stop validation anytime.
• Auto-scroll to the latest verified email entry.

• Re-import lists for re-validation or incremental updates.
• Easy integration with CRM / Email Marketing Systems / Lead Tools.

• Full source code included (C# .NET Framework 4.8).
• Clean modular structure: EmailValidatorCore, SmtpClientHandler, DNSResolver, UI Manager.
• No external dependencies or APIs — runs fully offline.
• Optimized for high accuracy and enterprise reliability.

• Fully offline operation — no external API calls or data leaks.
• Direct SMTP handshake for true validation (EHLO → MAIL FROM → RCPT TO).
• Encrypted logging and local-only result storage.
• Detects disposable, fake, and temporary email domains.
• Prevents false-positive Gmail validations (250 OK catch-all issue).

• Modern UI.
• High-DPI aware and multi-monitor compatible.
• Built-in real-time logs and progress visualization.
• Automatic summary report after task completion.

This status means the target mail server did not clearly confirm whether the mailbox exists. Some major providers — especially Gmail, Outlook, Yahoo, and iCloud — use anti-spam protection policies that hide real verification results during the SMTP handshake.

These servers intentionally return a generic response (such as 250 OK) for both valid and invalid addresses, so no external tool can know the actual mailbox status without sending a real email.

Reasons:

• Mailbox verification is disabled on the provider’s SMTP gateway (for privacy and anti-spam reasons).
• The server always responds with “accept all” behavior (Catch-All or Greylisting).
• Temporary 4xx responses or connection delays (rate limits, throttling, tarpitting).

Recommended actions:

• Treat “Unknown” results from Gmail/Outlook as potentially valid — not as invalid.
• Use the Trust Score and domain reputation data for confidence ranking.
• Re-check later from a different IP or network if needed.
• Combine SMTP verification with pattern-based analysis (MX, DNS, SPF/DMARC, disposable domain detection).

These ports are used for SMTP outbound email communication. If your software shows “Cannot connect” or “Timeout”, it usually means your network is blocking outbound mail traffic.

Common reasons:

• ISP / Hosting Provider Block: Many ISPs block port 25 by default to prevent spam sending. Some also restrict 465 and 587.
• Firewall or Antivirus: Local security software may block outbound SMTP connections.
• Company / Office Network Policy: Corporate routers or proxies can intercept and filter SMTP traffic.
• VPN Conflict: Some VPNs only allow HTTP/HTTPS traffic, not SMTP.
• Server-side Rate Limiting: The remote MX server temporarily refuses connections after too many requests.

Solutions:

• Try switching between ports 587 → 25 → 465 (the app supports adaptive fallback).
• Check and temporarily disable firewall or antivirus blocking rules.
• Try switching to another network (e.g., mobile hotspot, different ISP).
• Test connectivity using telnet smtp.gmail.com 587 or PowerShell Test-NetConnection -Port 25.
• For cloud or VPS environments, ensure the provider allows outbound mail ports (e.g., AWS, Azure, GCP often block 25).
• Manually open or whitelist ports 25 / 465 / 587 in your firewall and antivirus.
• Contact your ISP to request SMTP port access if permanently blocked.

This happens because most home or office networks block outbound SMTP traffic for security and anti-spam reasons, while VPS / Cloud servers are hosted in data centers with open mail ports and public IPs.

Detailed reasons:

• ISP Restrictions: Your Internet provider may block ports 25 / 465 / 587 on home connections, but cloud networks (AWS, Azure, Hetzner, etc.) allow them.
• Network Reputation: VPS servers use static, verified IPs that are trusted by most mail providers; home IPs are often flagged as “residential” or “dynamic.”
• Firewall / NAT / Router Filtering: Local routers or antivirus software can silently block or modify outbound SMTP packets.
• IPv6 or DNS Delay: Some home DNS resolvers and IPv6 stacks cause handshake timeouts with MX servers.

Solutions:

• Run the software on a VPS or remote Windows server for stable validation.
• Manually open ports 25 / 465 / 587 in your local firewall and antivirus.
• Switch DNS to Google DNS (8.8.8.8 / 8.8.4.4) for better resolution.

Before purchasing this software, please make sure you know how to check and test your SMTP ports (25 / 465 / 587). If your local network or Internet provider blocks these ports, the software will not be able to perform live SMTP verification.

Recommended test commands before purchase:

• telnet smtp.gmail.com 587
• Test-NetConnection smtp.gmail.com -Port 465

If both fail, please contact your ISP or network administrator to enable these ports, or use a VPN / SOCKS5 proxy that supports SMTP.

Even if your network cannot connect to SMTP ports (25 / 465 / 587), the software will still function normally. All other features — such as syntax validation, domain & MX lookup, DNS checking, Trust Score analysis, and report generation — will continue to work. Only the SMTP live verification step will timeout due to blocked connections.

✅ Summary: Port connection failure does not mean software malfunction — it only affects the live mailbox handshake process.

• ✅ Requires a stable Internet connection with open SMTP ports.
• ✅ You may also run it on a VPS / Cloud Server for better stability.
• ⚙️ If “Connection failed” or “Port unreachable” occurs, please check your firewall / ISP / antivirus before reporting an issue.

Super Bulk Email Verifier is not just a simple syntax checker — it’s a complete enterprise-grade email verification system that connects directly to mail servers, analyzes MX responses, SPF/DMARC configurations, and trust signals to ensure accurate, fast, and reliable results.

🧠 Stop wasting time and money on fake or unreachable emails — verify before you send.