[quoted text, click to view] > I have a webpage that sends out email via the server's local smtp
> service (configured to use a remote host).
(smart host)
[quoted text, click to view] > The email subroutine uses "on error resume next" to allow page
> submission to continue to process instead of halting the whole
> thing. Do generated emails generated & sent via CDO.Message
> completely lost in this case or do they get queued?
They are lost; they are not "sent" at all. If you stop trying to
communicate with the SMTP server at first communication failure
(instead of creating your own retry loop), there will be no automatic
retry.
There are 3rd-party mail components that have their own asynchronous
queueing mechanism, which essentially amounts to a
mini-outbound-server running within the component. This allows you to
call the object's send method and then continue with the next part of
your code, and the component will retry and invoke a callback when it
has a final result. But these types of features will typically not be
usable from short-lived/single-threaded/synchronous web applications:
the object may have its own internal queue, but if the entire invoked
object is destroyed when the page is finished loading, then any
asynchronous features are effectively gone. Some components may have a
shared memory area or interface with a service... but then you're just
running an alternate SMTP server.
Anyway, no matter, since there is next to zero reason for your
outbound IIS SMTP virtual server to go down. The engine can process
millions of e-mails per day without a service-level hiccup. Obviously,
the speed of your uplink will determine how fast the queue gets
emptied, but there is no reason to expect service-level failure from
an SMTP server dedicated to processing outbound mail.
