We provide email encryption services for a variety of customers. All of our email from three of our IPs has been blocked when sending to sophos customers. We are receiving messages like:
554 5.7.1 Service unavailable; Client host [199.60.232.32] is blacklisted. Visit www.sophos.com/.../ip-lookup.aspx to request delisting
554 5.7.1 Service unavailable; Client host [199.60.232.33] is blacklisted. Visit www.sophos.com/.../ip-lookup.aspx to request delisting
554 5.7.1 Service unavailable; Client host [199.60.232.34] is blacklisted. Visit www.sophos.com/.../ip-lookup.aspx to request delisting
When I go to that web page and enter the IP it says that the IP is not on any blacklist. Are there other steps that I can take to have these IP addresses unblocked?
