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Mail to Comcast is rejected and is returned with an error message containing the code BL001010. What does this mean?

Your mail could not be delivered because your mail provider is listed on Cloudmark Sender Intelligence (CSI), as well as the MAPS by TrendMicro Blocklist.  These are lists of mail providers who have been detected as sending spam.  Comcast uses these lists to protect its subscribers from receiving spam.

How do I get my email through?

It is important that your email provider is aware of their outbound spam problem to avoid being blocked by Comcast in the future.  When contacting your email provider, you should include the error message contained in the email that alerted you to this problem.  This error message contains important information to help your email provider resolve this issue.  To address this issue, either you or your mail provider can visit the CSI website by clicking here, and MAPS' website by clicking here, in order to have this block removed.