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Emails from Thunderbird to Hotmail addresses are bouncing back.

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It's just like the title says: for some reason, for the past two days, every time I send or reply to an email to someone with a hotmail.com address, I get a "Mail delivery failed; returning message to sender" message. The details of the email look something like this:

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:

 scuzz98@hotmail.com
   SMTP error from remote mail server after MAIL FROM:<dsiudara@sprynet.com> SIZE=20253:
   host mx2.hotmail.com [104.44.194.235]: 550 SC-002 (SNT004-MC9F6) Unfortunately, messages from 209.86.89.65 weren't sent. Please contact your Internet service provider since part of their network is on our block list. You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors.

This is for several different hotmail users, so I know it's not isolated to this one person.

Please help.

Thanks, Danny

It's just like the title says: for some reason, for the past two days, every time I send or reply to an email to someone with a hotmail.com address, I get a "Mail delivery failed; returning message to sender" message. The details of the email look something like this: This message was created automatically by mail delivery software. A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: scuzz98@hotmail.com SMTP error from remote mail server after MAIL FROM:<dsiudara@sprynet.com> SIZE=20253: host mx2.hotmail.com [104.44.194.235]: 550 SC-002 (SNT004-MC9F6) Unfortunately, messages from 209.86.89.65 weren't sent. Please contact your Internet service provider since part of their network is on our block list. You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. This is for several different hotmail users, so I know it's not isolated to this one person. Please help. Thanks, Danny

All Replies (1)

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The solution is in the error message. Contact your ISP because their network is blocked for spam.

This has nothing to do with Thunderbird.