client does not have permission to send at this sender (550)

Question

Hi, i using smtp class to send a mail but the method send return an exception.

The message is: client does not have permission to send at this sender (550)

this the call stack:

in Rebex.Net.Smtp.COvOkZ(String , String )
in Rebex.Net.Smtp.bUTESW(String , String[] , String , Stream )
in Rebex.Net.Smtp.BTPxIKZ(MimeMessage , Stream , MailAddress , MailAddressCollection )
in Rebex.Net.Smtp.Send(MailMessage mail, String sender, String recipients)
in Rebex.Net.Smtp.Send(MailMessage mail)

If configured the same mail with outlook and i don't have the same problem.

Best regards Enrico

Comments

Could you create a communication log produced using the Smtp object's LogWriter property ( as described at http://www.rebex.net/kb/logging.aspx ). You can post the log here or send it us to e-mail support@rebex.net.

Answer 1

This seems to be the Microsoft Exchange's 'Client does not have permission to send as this sender' error message. The most likely cause is that you used a From address in your message that was different from the e-mail address assigned to the authenticated user in Exchange. Using the same From address used in Outlook should solve the problem.

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