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Article PS01122780

501 Invalid Address error

Problem Description

When trying to send an email message with AspEmail, the following error is generated by the Send method:

Persits.MailSender.4 (0x800A0006)
501 5.5.4 Invalid Address

Other variations of this error for different SMTP implementations include:

501 Syntax Error

501 Invalid Address

501 malformed address

501 unacceptable mail address

553 malformed address


The most common reason for this error is failure to assign a valid email address to the mandatory From property:

Mail.From = ""

This error may also occur if a name instead of email address is specified for this property.

Another reason is invalid syntax in an email address passed to any of the methods AddAddress, AddCC, AddBcc and AddReplyTo.

Created: 2/8/2002 4:25:35 AM
Last Modified: 2/9/2002 3:29:05 PM

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