I appreciate all of the feedback. We eventually get Amazon SES to work by adding the following line to sitecfg.file. DEBUG_DMARC_REWRITE * This feature uses DMARC functionality to rewrite the "From" address on every message passing through LISTSERV so that all messages sent "From" [log in to unmask] This has the desired result of all email flowing and being delivered properly. At Vanderbilt we had also implemented an anti-phishing policy within the last few months that warns users the first time they receive a message from a new address. Somehow the confluence of these two changes has resulted in one our list owners seeing the following. [cid:image001.png@01D89DA9.7B4F5460] I told her this might happen at first, but then it should cease once people receive several messages from the same sender. She reported she sends messages almost daily and this has been happening for a month. I asked Microsoft about it, and was told they have an algorithm for determining when to warn users that they don't publish so it won't be abused. Any ideas or suggestions? Andy [Vanderbilt] Andy Richter Senior System Administrator, Hosting Services Information Technology | Vanderbilt University 615.343.4518 | [log in to unmask]<mailto:[log in to unmask]> From: LISTSERV Site Administrators' Forum <[log in to unmask]> On Behalf Of Barth, Michael Sent: Tuesday, June 14, 2022 8:58 AM To: [log in to unmask] Subject: Re: configuring LISTSERV to work with Amazon Simple Email Service (SES) My gut tells me it's the TLS changes that occurred with outlook. They started requiring TLS 1.2 and higher. You might be hitting a legacy route for that, or an invalid SMTP relay. I'd check into what those TLS requirements are From: LISTSERV Site Administrators' Forum <[log in to unmask]<mailto:[log in to unmask]>> On Behalf Of Phelps, Eli Jackson Sent: Tuesday, June 14, 2022 8:45 AM To: [log in to unmask]<mailto:[log in to unmask]> Subject: Re: configuring LISTSERV to work with Amazon Simple Email Service (SES) CAUTION: This email originated from outside of Indian Prairie School District 204. Do not click on any links or open/save attachments unless you recognize the sender's email address and know that the content is safe. ...Almost identical issue here too: We have hosted our own LISTSERV environment on-prem for almost two decades now. As of about 2 months ago all of a sudden no external partners can post on our lists either but, can receive from those same lists. Our mail exchange has been using ...mail.protection.outlook.com for the last several years. I've spent the last 2 months troubleshooting with numerous Microsoft engineers and we're just going in circles. Thanks, Eli Phelps ______________________________________________________ Eli Phelps Sys Programmer/Analyst III AFH Ntwrk Systems Spprt Srvcs ECU | Information Technology & Computing Services (ITCS) 209 Cotanche St. | Office Cotanche 101 | Mail Stop 229 Greenville, NC 27858-1125 Office: 252-737-4732 | [log in to unmask]<mailto:[log in to unmask]> | ecu.edu/itcs<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flinkprotect.cudasvc.com%2Furl%3Fa%3Dhttp%253a%252f%252fwww.ecu.edu%252fitcs%26c%3DE%2C1%2C7-NTKlTzYKBFv5ABiSZktd5AKIWWyHAnhnx6WI51e1PUtjgZdISIL-5_nHLaQ70zdOneECEpiW-0qGgSBj7saYH_n0175lPMz1kszsA4%26typo%3D1&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=Pj4GSgQcxY6X98txeyFrpNwmKpAmzzGkuxyho8s9Vq0%3D&reserved=0> [cid:image003.png@01D89DA8.4819DA30] _______________________________________________________ Work Shift: M-F 7:00-4:00 EDT/EST; Lunch ~12:00-1:00 Reach me online via Teams<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fteams.microsoft.com%2Fl%2Fcall%2F0%2F0%3Fusers%3Dphelpse14%40ecu.edu&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=qnqrkgdmrnfuXBUuxOO3FZFVABcKLDv1D0J7ZHXB5yo%3D&reserved=0> or Webex<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fecu.webex.com%2Fmeet%2Fphelpse14&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=Ojeoh1FswvQI4umKijzgYquuIDYlHGrQlasVvpMPV8w%3D&reserved=0>. Book time with me or our team.<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Foutlook.office365.com%2Fowa%2Fcalendar%2Fbcitcsucc%40studentsecuedu66932.onmicrosoft.com%2Fbookings%2F&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=NulUe%2B1QD0mHDiD4%2F8d2dKMRTh%2FdXHQzPCTjfR46QLw%3D&reserved=0> (no solicitation) From: LISTSERV Site Administrators' Forum <[log in to unmask]<mailto:[log in to unmask]>> On Behalf Of ? Nick Abiola-Bisiolu Sent: Tuesday, June 14, 2022 9:24 AM To: [log in to unmask]<mailto:[log in to unmask]> Subject: Re: configuring LISTSERV to work with Amazon Simple Email Service (SES) This email originated from outside ECU. Instead of using Amazon SES as your Listserv email gateway why not route the traffic to your domain gateway SMTP server to handle the outbound traffic. I noticed that your email is primary host is Microsoft Outlook. They might have a service similar to Google SMTP Gateway to support your domain SMTP traffic. Our Listserv is hosted on Amazon AWS and forwarded all outbound emails to our Google SMTP gateway successfully for many years now. Regards, Nick IEEE On Tue, Jun 14, 2022 at 9:14 AM Richter, Andy <[log in to unmask]<mailto:[log in to unmask]>> wrote: We have LISTSERV configured to work properly with Amazon Simple Email Service for messages that originate from Vanderbilt.edu<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flinkprotect.cudasvc.com%2Furl%3Fa%3Dhttps%253a%252f%252fVanderbilt.edu%26c%3DE%2C1%2CeVuamPTziCayXSKDVvFi0C6YLEEjIc2FijhPEd6jJrBw41Df1joPHe7_WnQsOLjCT_4RbKHIWqH5rdQscvR7p7v5Sy2YS608FzzeN3RNTnY8%26typo%3D1%26ancr_add%3D1&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=o7ThPJIgC1EtETRzvAABiAb5hl%2FbDJPFGpId%2Fo09VZk%3D&reserved=0> However, all of our LISTSERV messages that originate from our external partners are being blocked because we are unable to verify their email addresses to Amazon SES. If you have LISTSERV fully working with Amazon SES, I would appreciate any advice on what I need to do to make it fully work for Vanderbilt University. [Vanderbilt] Andy Richter Senior System Administrator, Hosting Services Information Technology | Vanderbilt University 615.343.4518 | [log in to unmask]<mailto:[log in to unmask]> ________________________________ To unsubscribe from the LSTSRV-L list, click the following link: http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTSRV-L&A=1<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fpeach.ease.lsoft.com%2Fscripts%2Fwa-PEACH.exe%3FSUBED1%3DLSTSRV-L%26A%3D1&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=YHKmskBZRAbiPytO2Cn%2BAha%2FwxBqfuf1fkkJ5sjDODg%3D&reserved=0> ________________________________ To unsubscribe from the LSTSRV-L list, click the following link: http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTSRV-L&A=1<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fpeach.ease.lsoft.com%2Fscripts%2Fwa-PEACH.exe%3FSUBED1%3DLSTSRV-L%26A%3D1&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=YHKmskBZRAbiPytO2Cn%2BAha%2FwxBqfuf1fkkJ5sjDODg%3D&reserved=0> ________________________________ To unsubscribe from the LSTSRV-L list, click the following link: http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTSRV-L&A=1<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Flinkprotect.cudasvc.com%2Furl%3Fa%3Dhttp%253a%252f%252fpeach.ease.lsoft.com%252fscripts%252fwa-PEACH.exe%253fSUBED1%253dLSTSRV-L%2526A%253d1%26c%3DE%2C1%2CShsKXW5BVLQrrcCKiprp_adJN7tAEzHb8hv0pgQ8I3va9GwI-wzKmX2210-YwHkkrFDTaJtxyYyrAQq34oVcevtLU_qkLG2lXfaTdqI0OlJZsJ44iX1EiKQSx68%2C%26typo%3D1&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=DWXzeBgtd7YMEj6rBPHEmy4QuMt6cAAVv2xiGd2n78k%3D&reserved=0> ________________________________ To unsubscribe from the LSTSRV-L list, click the following link: http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTSRV-L&A=1<https://nam04.safelinks.protection.outlook.com/?url=http%3A%2F%2Fpeach.ease.lsoft.com%2Fscripts%2Fwa-PEACH.exe%3FSUBED1%3DLSTSRV-L%26A%3D1&data=05%7C01%7Candy.richter%40VANDERBILT.EDU%7C8f8027e770524a70605a08da4e0df776%7Cba5a7f39e3be4ab3b45067fa80faecad%7C0%7C0%7C637908119147335060%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C2000%7C%7C%7C&sdata=YHKmskBZRAbiPytO2Cn%2BAha%2FwxBqfuf1fkkJ5sjDODg%3D&reserved=0> ############################ To unsubscribe from the LSTSRV-L list: write to: mailto:[log in to unmask] or click the following link: http://peach.ease.lsoft.com/scripts/wa-PEACH.exe?SUBED1=LSTSRV-L&A=1