SMTP Verification Fails with Certain SOCKS5 Proxies

[emilianocalzada]

Hello, as other users have mentioned: #51, #44 (comment)

I've identified an issue where email verification fails when using specific SOCKS5 proxies. I've created a test SOCKS5 proxy that consistently reproduces this error, which I'm happy to share to help debug the problem.

ERROR EOF : EOF

To verify this is a library-specific issue, I've created a separate script that performs SMTP checks manually using SOCKS5, which works correctly (code here: https://github.com/emilianocalzada/smtpverif/blob/main/main.go). This suggests there might be an implementation detail in the library that needs attention.

I'm actively investigating the root cause and willing to collaborate on a fix. Let me know if you'd like access to the test proxy or need any additional information to reproduce the issue.

*Note, this is not a proxy server issue, i have used this same proxy with reachable and it works well. i have also sent a command by using terminal and it works, PORT 25 is opened 👍