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I currently still developing email blast software. Last time i sending blast with quota 10.000 emails/hour. I got notification from my server admin if my IP is blacklisted because of spam. Can you please suggest me, what is the right policy how much can we sending email blast per hour?

I do understand email blast server my become blacklisted by many reasons, but for now i looking for "normal" max sending email per hours how much by IP.

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There's no RFC-determined limit on this; no single value that holds good all over the internet. You will have to ask the people who are running the blacklists, and your admins. – MadHatter Dec 10 '13 at 15:06
Are you sending spammy content? Are you sending to users who didn't double-opt-in? – ceejayoz Dec 10 '13 at 15:21
@ceejayoz Nope, it's not spammy content. All the user i send email is the user registered through my subscriber system. Can you explain what is double-opt-in? – GusDeCooL Dec 10 '13 at 15:32
@GusDeCooL Please don't take this the wrong way, but if you don't know what double-opt-in (sometimes called "Confirmed opt-in" - does that sound more familiar?) is you probably need to go do some more research on bulk emailing practices before writing your own email blasting software... – voretaq7 Dec 10 '13 at 21:03
up vote 3 down vote accepted

It's a very complex business and there's no be all and end all value. Your IP addresses need to be initially 'warmed up' and you can slowly up your emails/hour rate as time goes on. Your sender should also take account of the messages returned by the destination SMTP servers and should exponentially 'back off' on the send rate to a particular domain (e.g. when servers request this.

You can also register for notifications from services like Yahoo mail when someone marks your e-mail as 'spam'. This will allow you to unsubscribe them.

We run our own sending platform utilizing PowerMTA but it's taken many years of tuning to get it to where it is now. I would highly recommend using Amazon Simple Email Service as this takes care of these considerations for you.

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Wow, thanks pil. Yes, at first i set it at 1.000/hours and get no problem. just today i up it into 10.000/hours and get problem. i will look at amazon simple email service. can you give me link where i can register for yahoo mark spam? – GusDeCooL Dec 10 '13 at 15:35

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