False Negative

Hi,
Many many thanks for this excellent project. I tried it. Works great. But in some cases it is providing wrong results. When the server is blocking your server then it will mark that address as Invalid. But it should tell that verification is not possible with that address. Here is a conversation i got:

Resolving host name "mx.rediffmail.rediff.akadns.net"...
Connecting to host address "202.137.234.30"...
Connected.
S 220 f4mail-234-183.rediffmail.com ESMTP
C HELO streamizsupport.in
S 250 f4mail-234-183.rediffmail.com
C MAIL FROM: <info@streamizsupport.in>
S 250 ok
C RCPT TO: <bhavik_hingrajia@rediffmail.com>
S 553 sorry, your envelope sender is in my badmailfrom list (#5.7.1). REF-ID : MBFD
This host states that the address is not valid.

Why it is saying the address is not valid. The ID is valid and from the conversation rediffmail blocked our server. So it should mark it as test not possible.

Can you please provide a solution on this.

Thanks.

The result means that the specified destination address is invalid to deliver from the sender address your specified.

It may be valid to other addresses but the class has no way of guessing that unless you call it specifying a different sender address.

The server is returning code 553

Is it possible to change the code in emailvalidation.php to mark this address as "Test not possible"?

If it can be done then this will be a full working amazing script.

Please advise.

It seems it is not clear for you what happens.

The destination SMTP server of the tested email address is saying that if you send a message from the sender address that was specified, it would reject the message.

It does not make sense to change the class to treat code 553 as something else than invalid destination email address because that is the same code most servers return when they reject messages to the tested addresses.

Furthermore, nothing indicates that the tested address is valid, so you should treat it always as invalid.

If that is not the response that you want, you need to change the sender address.

Excellent.

It does not make sense to change the class to treat code 553 as something else than invalid destination email address because that is the same code most servers return when they reject messages to the tested addresses.

This is the answer i was looking for. Many thanks for clearing this.

The problem is after some time the sender address will get blacklisted. So it is not possible to get correct result. Also we always have to monitor the code to understand the address is not really invalid but our server is blocked and that is why it is showing as invalid.

I am still looking into the conversation result and desperately trying to find a way out to mark address as Test not possible. Otherwise it will be difficult to use this class because it will mark Valid address as Invalid if your server gets blocked.

Thanks.

Yes, in general mail servers given even less information regarding why messages cannot be delivered, so your application should not rely on this method to determine if a specific sender email address is being blocked or it is the tested delivery address that it is not valid.