Email bouncing nightmare - please help!

  justjill 08:58 02 Sep 2009

I posted here a while ago about emails from our business account being rejected as spam by recipients. Our web hosts said that someone else sharing the server had been spamming and that was the problem. Someone here advised me to try AuthSMTP and we did and it has sorted out most problems but we've still got a few.

Our emails to our most high profile customer are bouncing again and we look like idiots. We asked the customer if they could change their settings to accept our emails and their IT department told us that we're on a block list at and we'd need to contact them.

The bounce message says:

SMTP error from remote mail server after end of data:
host mail.********* [***.***.**.***]:
550 5.7.1 This system has been configured to reject your mail. An IP address (**.***.***.***) found in the message's 'Received:' headers is listed by the lookup site ''.

I looked up our IP address on and it says it's not in a block list, it's just listed in the pbl and that we need to enable mail authentication in our email client (we use Thunderbird). I did this and it allowed us to send email to the customer but we can't receive any mail as we keep getting an error saying the email account doesn't support authentication.

The only way I can think to get around this is to turn on authentication every time we email the customer and then turn it off again, which is a bit Heath Robinson and which we can't do on the iPhone, so not ideal.

Does anyone know of a way to sort this out once and for all which doesn't involve getting a dedicated server?

Many thanks in advance :)

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