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501: Too many syntax or protocol errors whilst sending a mass email via BCC

slug0r asked
Medium Priority
Last Modified: 2009-11-23

I'm getting a error message 501: Too many syntax or protocol errors whilst sending a email to 20 people in BCC.

Every time i send this email it says it has been interrupted.

What would cause this? what is the solution?.
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Top Expert 2010

Greetings, slug0r.

Are you sending via an Exchange server or an SMTP server?  Is your mail service hosted?

Hi slug0r!

This error message usually indicates a problem on the receiving end, not on your end.

The basic idea is that your server asks the e-mail server on the other end what 'languages' it speaks. The server on the other end responds with what it thinks it is allowed to speak.

When your e-mail server tries to send the message, a router blocks the message from getting through, so the message bounces back to you. Technically, it is blocking communication via the ESMTP protocol.

The solution to this problem is to contact the person to whom you are trying to send e-mail and ask that person to contact their e-mail postmaster or system administrator. The postmaster or system administrator needs to change the router's configuration so that it allows ESMTP communication to take place.

HTH, Cheers.


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