Thanks again. You were very helpful. That DynECT service seems to be exactly what we need.
One last thing I'm going to bother you with. When I sign up for an SMTP service, how can I check that our emails sent out through them don't get thrown out as spam as well? In other words, how did you test that Bluehost IPs as spam for me?
Send yourself an email then find the mail servers IP from the headers hten check it here - Email Blacklist Check - See if your server is blacklisted
I just signed up for the Dyn account as you suggested. Can I send you another email and have you look at the headers?
SPF pass and a clean IP.......all looks good.
Just to give everyone a quick update. I spent a lot of time dealing with this issue and would like to share my experience.
As I said earlier I signed up with DynECT and I like their support, they reply to emails within a couple of hours (during business week) and my emails sent through them get delivered generally reliably. But it comes with one serious limitation -- they do not provide APIs for sending emails via scripts. They open two ports for SMTP connections, but unfortunately my dumb web hosting provider (Bluehost) blocks all outgoing ports from PHP scripts, so I can't send emails via DynECT using a script. (I need this for user email registrations.)
Later, just by accident I stumbled upon mandrill.com that is an awesome solution to my problem. They allow up to 12,000 emails a month for free with the starting rate of 25 an hour, which is promised to be increased if they see no abuse. They also provide a JSON-based API that bypasses all these ridiculous Bluehost restrictions. So I can now send emails via a php script. Awesome! I really like their service. Only if they provided a hosting service, I'd definitely switch from this horrible service I get from Bluehost...
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