For a lot of reasons, you don't want to try sending mail to every address you've harvested from your inbox. First of all, some addresses are probably personal, and you might not want to send your business newsletter to everyone in your family. Next, many addresses that appear on your list are administrative addresses. Finally, some of the addresses are no longer valid.
Verifying E-mail Addresses
Avoid sending newsletters to bad addresses else you will have to deal with bounced messages. A list of addresses harvested from your inbox, can roughly contain a third bad.
We suggest that the first thing you do is verify the addresses using a tool like Email Verifier. With Email Verifier, you import your list of harvested addresses, and click "Start." The tool is fast, but not instantaneous. Speed depends on the size of your list, your connection, and the speed of the Web. If your list is really big, run it at night.
You need to have access to port 25 for this to work. If you're operating within a restrictive firewall, as most users of large ISPs are, then you won't be able to use this tool. You need either unrestricted access or a hole in your corporate firewall for port 25 access. This software does what your SMTP e-mail server does, which is confirm that the person exists before sending the message. Smaller local ISPs don't use to block port 25.
For some addresses, such as AOL, Yahoo, Hotmail, and other non-SMTP mail, you can't verify whether or not the address is good. The mail server won't cooperate, so you can set the options of Email Verifier either to assume they're all good or assume they're all bad. You won't know definitively until some bounce.
There is a demo version of this software available here but you can't save the results. When you've completed the verification using a licensed copy, you can export the good addresses to a file. This will be the list you use for your newsletter.
Unfortunately, verifying the addresses using a tool isn't enough. Unless your addresses came from a customer database, you probably want to manually remove all administrative addresses such as orders@ anything, support@ anything, listserv@ anything. There are more, but that's a good start. If you don't remove these, then you'll receive automated replies from a lot of places. When you're doing the manual clean up, you can also remove any personal addresses to which you don't want the newsletter going.
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