It has come to our attention that our mail server's IP has been blacklisted by more than one entity. As such, messages being sent to your @cs.brown.edu address or through our internal mail server may have been sent to the Spam folder.
To mitigate this situation, we have switched to the backup server which reports a different IP address. But, this workaround may only be temporary as it is possible that this IP will be blacklisted, as well.
We are working on a more permanent solution. So, please, be vigilant in checking for message wrongly marked as Spam and continue to be patient with as we try to discover the root of this situation.