I am also having problems since moving my hosting to new servers/IP, some yahoo emails go through right away (Usually at night) and others bounce back.
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Could not deliver message to the following recipient(s):
Failed Recipient: bryweb@yahoo.com
Reason: Remote host said: 421 Message from (66.196.##.###) temporarily deferred - 4.16.50. Please refer to http://help.yahoo.com/help/us/mail/defer/defer-06.html
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Yahoo whitelisted my IP before but now refuse too because I host multiple domains under (1) IP - this was their reply;
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Thank you for writing to Yahoo! Mail.
We cannot systematically exempt your mailings from our SpamGuard technology since the IP address of the server appears to be a shared domain mail host and have multiple clients sending email. We will maintain the current information in our database as it is configured.
This allows delivery of your mailings to oscillate between the Inbox and the Bulk Mail folder as Yahoo! users choose.
Please keep in mind that our SpamGuard technology will continually monitor user feedback pertaining to emails coming from your mail server(s), and as such, the user feedback we receive will be one of the factors that influence where your emails are most appropriately delivered. Our studies have indicated that when users see messages incorrectly categorized, they notify us within hours of delivery.
We do recommend that if you maintain several clients or company lists (especially for an ISP/ASP/ESP) to segregate your clients to different IP addresses. This ensures that users are marking each company on its own merits. User notifications to us may become hazy should they see both spam and legitimate mail from the same IP. In cases like these, the end result will likely be that spam will override the legitimate mail.
If you implement significant changes to your mailing practices, feel free to contact us again. You may refer to the Help page below for some information and general guidelines that we have found to be effective in maintaining good mailing lists:
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This Sucks since they whitelisted me before and I had no problems.
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