From time to time, I get an error message from my email software and am unable to send my message out, why?

What you have experienced has been documented on our Web site's FAQ (Frequently Asked Questions) section for years. Specifically, it's in the FAQ "I can't send outgoing email, why?". The relevant section is quoted below for your convenience:

Are you using an ISP that enforces a very strict mail proxy policy (i.e whenever you send outgoing messages, your ISP's setup unconditionally route your outgoing mail through the ISP's own mail servers? AOL, EarthLink/MindSpring, Comcast, MSN, Netzero, Juno all do this in parts or all of US. Such a policy usually is put in place for anti-spam purposes). If your ISP has this mechanism in place in your area, you will be blocked by your ISP from using our mail servers to send outgoing messages.

Please note that the following are all external actions that are beyond our control. We can do nothing about them!

• whether your ISP implements such a policy uniformly in every area it serves, or just some areas, or not in any areas so far; and
• when it introduces such a policy into a service area

As long as you use an ISP that has such a policy implemented in your area, You most likely will have to use a designated outgoing mail server specified by your ISP for sending messages.

As explained above, this ISP restriction may not be implemented uniformly. That's why you experience it sometimes, but not all the time. Regardless AZC has no control of it. So, to ensure reliable operation for sending mail when using your ISP for Internet access, you most likely should always use your ISP's mail server to send outgoing messages.

As long as you set the Reply-To: field of your mail client (Outlook, Eudora) to your domain name, you still give your correspondents the opportunity to send replies to a stationary address, reaping the benefits of using your domain name for email.

The fact that your outgoing email messages may carry your ISP's domain name is not really that important. One can always send outgoing messages from different places, as long as s/he has access to an mail server. But, having a fixed return address is critical for both of you and your correspondents - you don't need to inform your correpondents of "new" email addresses from time to time, and your correspondents don't need to keep up with your possibly frequent email address changes.

Switching email addresses often is not an effective way to avoid spam in any sense; it's actually very counterproductive. Remember obsecurity is not a substitute for security, unless you never expose your email address, sooner or later it will be captured by a spammer and subsequently eploited.

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