On April 8th Yahoo.com made a change that will prevent your email from being delivered to your list if you are useing a Yahoo email address as your “from” email within your responder system. They have implemented the DMARC system.
DMARC is a well-respected organization. Most of the top ESPs, like gmail and hotmail respect them as well. ESPs will look for messages with a “From” address using an @yahoo.com domain and block delivery.
If you choose to use a Yahoo email address as your “From” address in your autoresponder, you will see a decline in your deliverability.
You can read about DMARC here: http://www.dmarc.org/
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