How do I set up a mass email without having it blocked?

Yes, this is true not sure on the exact email condition. What can you do is to schedule emails. or if you really want to send multiple emails, you need to set-up a mail server dedicated in sending this mails. I suggest also to put privacy policy on your website for your domain and put a disclaimer that your customers really accepted to receive subscription based emails to you. You may IM me if you need help.

Many mail servers operate spam filters.

They have many different rules for what counts as spam (unwanted emails)

I have had emails rejected because they contain the text inside a table!

The only reliable way to send emails is to send them

a) one at a time

b) without any complex html formatting

c) from a non-spam listed domain (so yahoo would be out)

d) to people who have agreed to put you in their mail server "white list".

The white list is a list of authoised contacts that can be edited and will result in your email always getting through.

It is a pain in the a** - but then so is having an inbox full of spam. Unfortunately the efforts of many companies to stop all the spam means that legitimate emails can have trouble getting through.

you have to set your setting on your email account to filter out that kind of mail maybe set the level higher or only allow emails from people in your address book

use a real e mail and buy a premium e mial service with a few gigs of storage

don't use yahoo, use a proper email service.