We have received several reports over the weekend that customers email has been flagged as spam by some receiving mail servers.
Bounce backs included errors such as:
<– 554 The IP Address of the sender (220.127.116.11) was found in a DNS blacklist database and was therefore refused.
<– 550 Email blocked by bl.spamcop.net (in reply to RCPT TO command)
On closer investigation it appears there was a system outage at the Cisco SpamCop DNS-based blocking service and the underlying cause was that the spamcop.net domain name had failed to be renewed.
More information on this issue can be found at the following link: