Chance of email NOT being received?

[Tom]

Windows XP Pro SP2 all MS updates
Outlook 2003 SP2 all MS updates
From email: (e-mail address removed)
To email: (e-mail address removed)
Delivery receipt turned ON
Read acknowledgement turned ON


I have a situation that the (e-mail address removed) is indicating they
did not receive an email from me a couple of days ago (9/5/2007). I sent the
email with delivery and read boxes checked and with high importance on the
email.
I received an acknowledgement of delivery at the same date and time that I
sent the email. The read acknowledgement was sent a couple of hours later
back to my email address also.
There was nothing to indicate the email bounced or delayed in any message to
me.
So, how can I be 100% sure that the email was received and read (displayed)?
TIA,

 

[DL]

You cannot, unless some person actually replies

 

[Tom]

Ok, in THIS case I received an acknowledgement of delivery AND and
acknowledgement of "read". So, why can't I be 100% sure then?
TIA!

 

[DL]

I was basing my answer on the fact that not all servers permit read
receipts, or that some firewalls will block them, or that some people ignore
them.
As such the only way to be sure is if some person physically acknowledges
the mail

 

[Tom]

So, if I can understand your comments you're essentially saying that if there
is NO response then I can't be 100% sure. No problem here.
However, in this specific situation I did receive a response. Hence, I
should be 100% sure the email was 1) delivered and then 2) opened ("read") as
I have specific responses to indicate both of these.

Is this a correct conclusion that I can draw from your comments?

 

[DL]

Unless some 'real' person physically replies to your mail, with an
indication it has been read, or at the very least contains your thread in
the response then you cannot be sure.

In your case as you have had "specific responses" it, must have been both
received & read