Topic: All mail to Yahoo is bouncing

[calisun]

All the mail I send to yahoo, I get it send back as undeliverable with following error message:

-----------------------------------------------
Hi. This is the qmail-send program at mydomain.com.
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

<my-friend@yahoo.com>:
Connected to 66.196.97.250 but greeting failed.
Remote host said: 421 Message from (##.###.###.##) temporarily deferred - 4.16.50
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when I search for error 4.16.50 it tells me:
   1. the message you attempted to send exhibited characteristics indicative of spam,and/or
   2. emails from your network have been generating complaints from Yahoo! Mail users.



I don't send out any spam at all, so there is non way anybody would complained.

So is this something that is caused by SME server because of the message: "Connected to 66.196.97.250 but greeting failed" ?

I am not sure if it makes any difference, but the email in question is not send from my primary domain, it is from one of my virtual domains.

[Stefano]

hi

are you using your isp's smart-host to send mail?

do you have a dynamic ip?

Ciao
Stefano

[janet]

calisun

Yahoo and many others ISPs/Internet services have got quite tough with email to try and reduce spam etc.
They have strange algorithms to reject mail.
Probably your server does not have reverse DNS configured and yahoo are therefore rejecting email from your server.

You can go to Yahoo website and lookup the tech support pages and get your server added to a list of acceptable sending servers. You will need to provide significant information about your server though.



A workaround is to send email via your ISP's smtp server, the setting is in the server manager E-mail panel.

[calisun]

I used to send email through comcast mail server, and everything was fine until comcast blocked port 25, so I moved my server to a co-location facility.
So now I have a static IP. 
It seems like yahoo is the only one that kicks my mail back, hotmail, gmail and lycos works fine.

Mary, I will look into reverse DNS and post back.

[dave simmons]

I had this problem a few months back.  In my case (and hopefully yours) it will sort itself out. 

My understanding of the system is as follows:  Yahoo defers delivery - doesn't completely refuse it -  and sends a message back to your mail server.  Your mail server then tries again to send the message, which succeeds.  Yahoo does this to stop spam, because spammers usually use a false sender address, and therefore the defer delivery message doesn't get back to the right place, and the mail server doesn't re-try.

We also didn't have SPF records in our DNS records.  Adding these may also have helped.