Sent 20 emails to person in mailing list - help.

This is my first time sending out email using a php script. Unfortunately, I bodged it up. There were 20 people in my batch mail job. The first person got 1 email, the second person got 2 emails and so on. That means that the last person in the list got 20 emails!

I ran this script on two sets of 20.

It's rude.

What are the chances that my server will be blacklisted as sending spam? I imagine that everybody in that list will flag my messages as being spam (well, except for one person). That's potentially around 400 spam emails.

BTW, these people had consented to receiving email.

First thing.

Send an email to all 20 people stating that you stuffed up and apologise for the inconvenience caused.

Second, create 2 new email addresses (gmail, hotmail, whatever) and use them to test your email script. Make sure it only sends 1 email to each account for each email that should be sent. Then once you've fully tested the script put it back live with the true email addresses.

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Blacklisted wise - Unlikely if it was only sent to 20 email addresses.