One of the nice features of Outlook is that it allows a sender to request a receipt from the receiver confirming delivery of email. Most often this can include not only delivery of email but also that the email has been opened suggesting but not guaranteeing it was also read. At the very least the sender can be sure that the email was not lost due to some arcane filter or virus control.

This can prove to be a useful feature in the communication process and also remove any doubts of communicated messages should the communications end up in a courtroom setting.

As always with software applications, in this case Outlook, you can still encounter problems. One of the problems reported with receipt delivery is that some users have experienced problems when sending their read receipt notifications. Specifically, responders have reported time-out errors such as a 0×8004210B operation time-out error message in Outlook 2000 or 2003.

During the process of opening an email message sent with a delivery receipt request users can choose to send a receipt. It is at this time that Outlook can pause for several seconds. Then the user will receive an error message such as:

“Task ‘ServerName- Sending’ reported error (0×8004210B): ‘The operation timed out waiting for a response from the sending (SMTP) server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP). The server responded: (IP Address) Client does not have permission to Send As this sender.”

If your end user is receiving this type of error message then you’re going to need an email administrator, specifically an Exchange administrator, to check the access authentication settings on server. When Exchange 2000 Server is installed and configured it has a default setting for the anonymous access authentication parameter as “on”. If the Exchange Server is using Simple Mail Transfer Protocol (SMTP) and this parameter is turned “off” then this can cause the above error message to be displayed and also cause the block of the receipt delivery response from the client.

The real crux of the problem is that the Outlook 2000 client is sending a “null” address to the Exchange server as the read receipt email address. Although this is within guidelines as per Request for Comments (RFC) 2298 it still causes a problem on the receiving end of the reply at the Exchange server. This is because Exchange 2000 incorrectly processes a reply that has a “null” address in the “From” address field if anonymous access authentication is turned off.

If you are using an Outlook 2002 client then you will not have this problem. Instead of substituting a “null” address for the “From” address as in Outlook 2000, Outlook 2002 will keep the original “From” address from the originating SMTP email. Thus the Exchange server will not experience an error situation. However, this error message will occur if the client is Outlook 2003 as it uses the same method for replying to a receipt required email message as Outlook 2000 does.

If you’re back at these rev levels then there is a hotfix available from Microsoft: the August 2004 Exchange 2000 Server Post-Service Pack 3 update.

There is another situation where you can receive the 0×8004210b error message and that is if you are sending SMTP email messages from an account that is using the Post Office Protocol (POP3) and also using the Secure Socket Layer for secure communications in Outlook 2002.

Your end users may receive the following error message:

“Sending and Receiving’ reported error (0×8004210B): The operation timed out waiting for a response from the sending (SMTP) server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP).”

Note that this error message may show up in the client’s outbox.

Again, Microsoft has provided a service pack to correct this error: Microsoft Office XP Service Pack 1.

There are other conditions which can cause Outlook to produce the 0×8004210b error. For instance, if your client computer is running the Symantec Norton SystemWorks application it can cause the error to be produced.  Or if the client system had the Freedom Security Zero-Knowledge Firewall software installed it will be possible for the 0×800421b error to happen. However, there are updated versions and reconfiguration instructions on the Symantec web site to correct these situations.