Why do members with Yahoo, Hotmail, AOL, and other email addresses sometimes complain that they do not get emails from the MLM Software?

This is most likely due to the following factors:

Filtered to Junk Mail:

The email might be sitting in the member's 'junk mail' folder. It may have been filtered there by the mail client at the member's end.
Long lengths and having the company name in the address makes it extremely likely to have a high spam index on incoming emails, reducing the deliverability to that email address. For example: prettylongname.extremelylongcompanyname@yahoo.com. You might wish to abbreviate long email addresses like this.

Email Service is blocking content:

Yahoo, Hotmail & AOL regularly bans MLM content before it ever gets to the user. Should the recipient want to increase deliverability, it is highly advisable to use Gmail, or better yet, a real Internet Service Provider address that will not be so harsh on content containing MLM information.

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