Hi Dan, To my understanding, the Hotmail side and the Microsoft 365 side (protection.outlook.com) have different blocklists and different teams managing them. What has changed recently is (I think I saw posted here) that Hotmail flow is now getting routed through the protection.outlook.com infrastructure.
Sounds like you got the block notification from the Microsoft 365 side (because of routing) but perhaps the real block is on the Hotmail side of the house? All the best, Mark _________________________________________________________________ L. Mark Stone, Founder North America's Leading Zimbra VAR/BSP/Training Partner For Companies With Mission-Critical Email Needs ----- Original Message ----- From: "Dan Mahoney (Gushi) via mailop" <mailop@mailop.org> To: "mailop" <mailop@mailop.org> Sent: Thursday, August 17, 2023 5:41:32 PM Subject: [mailop] Hotmail's Blocklist and S3150 Hey there all. Dayjob (ISC -- BIND, F-root, DHCP, those guys) just spun up a new ip block to put a few F&F/Employee VMs on. We are the ISP -- this is our netblock space. We've owned this block for a while, just haven't used it recently, and we've never really used it for *any* spam sending purpose. One thing I'll note is that it looks *LIKE* an RFC1918 ip, but it's not. (192.158 versus 192.168). One of them tried to send mail and got this block message (note, all domains are intaxct, but I have changed a letter in the uer-portion to stop it from getting picked up by harvesters). Aug 16 14:41:20 mail postfix/smtp[7844]: D47CA7A4672: to=<busanroser...@hotmail.com>, orig_to=<busa...@dragon.net>, relay=hotmail-com.olc.protection.outlook.com[104.47.56.161]:25, delay=1.9, delays=0.08/0.02/1.7/0.15, dsn=5.7.1, status=bounced (host hotmail-com.olc.protection.outlook.com[104.47.56.161] said: 550 5.7.1 Unfortunately, messages from [192.158.252.15] weren't sent. Please contact your Internet service provider since part of their network is on our block list (S3150). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. [CO1NAM11FT106.eop-nam11.prod.protection.outlook.com 2023-08-16T21:41:20.664Z 08DB9E137B1F64A7] (in reply to MAIL FROM command)) Aug 16 14:41:20 mail postfix/smtp[7844]: D47CA7A4672: to=<busanroser...@hotmail.com>, orig_to=<busa...@dragon.net>, relay=hotmail-com.olc.protection.outlook.com[104.47.56.161]:25, delay=1.9, delays=0.08/0.02/1.7/0.15, dsn=5.7.1, status=bounced (host hotmail-com.olc.protection.outlook.com[104.47.56.161] said: 550 5.7.1 Unfortunately, messages from [192.158.252.15] weren't sent. Please contact your Internet service provider since part of their network is on our block list (S3150). You can also refer your provider to http://mail.live.com/mail/troubleshooting.aspx#errors. [CO1NAM11FT106.eop-nam11.prod.protection.outlook.com 2023-08-16T21:41:20.664Z 08DB9E137B1F64A7] (in reply to MAIL FROM command)) We reached out to MS, requested a delist, To which MS responded: === Hello, Thank you for contacting Microsoft Online Services Technical Support. This email is about ticket number [number], which was opened regarding your delisting request for [192.158.252.15]. It appears that the IP you submitted is not currently listed on any of our block lists. This may be due to an earlier delisting request that has already been processed. If you continue to receive Non-Delivery Receipts (NDRs), or "bounce messages," that indicate that the IP address is still blocked by our spam filtering system, please forward one of the messages to us and we will investigate further. Thank you again for contacting Microsoft Online Services technical support and giving us the opportunity to serve you. ==== We are continuing to receive these. Is there some magic incantation I need to know. Shiboleet! (Help, plz). -Dan -- --------Dan Mahoney-------- Techie, Sysadmin, WebGeek Gushi on efnet/undernet IRC FB: fb.com/DanielMahoneyIV LI: linkedin.com/in/gushi Site: http://www.gushi.org --------------------------- _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop _______________________________________________ mailop mailing list mailop@mailop.org https://list.mailop.org/listinfo/mailop
