Dear all,
I am a new Office 365 user and today I was trying to finish our office's move from our own old Exchange server to Office 365. I have therefore followed the instructions provided by Microsoft and I have pointed the MX record of our domain to Office 365. The domain is still being hosted by the German domain provider Strato. After verifying the domain I was following the following instructions: http://community.office365.com/de-de/wikis/administration/konfiguration-und-nutzung-von-office-365-bei-strato.aspx
At first sight, the move seemed to be successful: Emails are now being delivered to our Office 365 accounts instead of the old Exchange server. However, the Office 365 mail server is now refusing all emails from one of my private email accounts (while other emails are still being delivered successfully). The emails from this private account are sent back with the following message:
Undelivered Mail Returned to Sender
This is the mail system at host [my_private_email_hoster]. I'm sorry to have to inform you that your message could not be delivered to one or more recipients. It's attached below. For further assistance, please send mail to postmaster. If you do so, please include this problem report. You can delete your own text from the attached returned message. The mail system <emailaccount_at_office365>: host [our_mx_record][microsoft_ip] said: 550 5.7.1 Service unavailable; Client host [client_ip] blocked using Blocklist 1, mail from IP banned; To request removal from this list please forward this message to delist@messaging.microsoft.com and include your ip address [client_ip] . (in reply to RCPT TO command)
Could you please explain to me what I can do? I have already tried putting [client_ip] on the white list in Office 365. It had no effect.
Kind regards,
cp