When trying to send an email message with AspEmail, the following error
is generated by the Send method:
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
Mail.From = "email@example.com"
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