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I'm running on Rackspace Cloud Servers and I've just setup a CentOS build and installed iRedMail. The problem is, 90% of the email I'm sending gets blocked and I get the error in my maillog:

NOQUEUE: reject: RCPT from unknown[]: 450 4.7.1 <>:
Recipient address rejected: Policy Rejection- Please try later.; 
from=<> to=<> proto=ESMTP helo='<>

For spam reasons I've taken out the real emails and put in pseudo ones.

I asked the technical support for some help and it wasn't much help. I've setup the SPF and TXT records but still no luck.

Any tips on what I could try or what I should look at or is this a ridiculous too open a question with too many things that could cause the issue?

Any help would really be appreciated. This is my first time setting up postfix from scratch :|

edit: somebody just told me that the emails are being 'greylisted' by my postfix setup to avoid being spammed.

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just thought I'd add - the emails do seem to eventually come through... is that weird? so they are being stopped for some reason, then sent later through dovecot – willdanceforfun Dec 5 '09 at 3:22
up vote 1 down vote accepted

you mention SPF and TXT records, but forward and reverse DNS need to be correct as well.

edit: easiest way I know to test:

dig -x +short `dig +short`

This should return "". If it does not, then separate the two commands:

dig -x your.ip.address

to see which or both is not working correctly.

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thanks for that. would you mind elaborating? how do I check if they are correct? – willdanceforfun Dec 5 '09 at 7:01

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