{
  "is": "issue",
  "title": "German SMTP blocked by Microsoft",
  "body": "\u003cp\u003e\u003cem\u003eFixed\u003c/em\u003e - It\u0026rsquo;s been over a week and we\u0026rsquo;ve seen no blocks of the new server IP by MIcrosoft, so we consider this to be resolved. \n  \u003cspan class=\"faded\"\u003e(15:04 UTC — Jan 17)\u003c/span\u003e\n\n\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eWatching\u003c/em\u003e - We informed Microsoft of our findings and the corrective action we\u0026rsquo;ve taken but we\u0026rsquo;ve still received no further communication from them.\u003c/p\u003e\n\u003cp\u003eTo work around this we\u0026rsquo;ve moved smtp.de.opalstack.com to a new IP address. Customers do not need to change any settings - the DNS change should propagate automatically within the hour.\u003c/p\u003e\n\u003cp\u003eAfter the DNS change has propagated, customers should be able to send mail to email addresses that are hosted by Microsoft.\u003c/p\u003e\n\u003cp\u003eWe\u0026rsquo;ll leave this incident open and will continue to monitor. \n  \u003cspan class=\"faded\"\u003e(16:28 UTC — Jan 6)\u003c/span\u003e\n\n\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eIdentified\u003c/em\u003e - We\u0026rsquo;ve still not heard from Microsoft but we believe we\u0026rsquo;ve identified the activity that triggered the block and are taking action to mitigate it at this time.\u003c/p\u003e\n\u003cp\u003eWe\u0026rsquo;ll notify Microsoft of the actions we\u0026rsquo;re taking and continue to hold on for a response. \n  \u003cspan class=\"faded\"\u003e(23:16 UTC — Jan 5)\u003c/span\u003e\n\n\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eInvestigating\u003c/em\u003e - We\u0026rsquo;re still awaiting a response from Microsoft and have reached out to them as a reminder. \n  \u003cspan class=\"faded\"\u003e(16:32 UTC — Jan 5)\u003c/span\u003e\n\n\u003c/p\u003e\n\u003cp\u003eOn January 3 2022 at 20:47 UTC Microsoft began blocking mail sent from smtp.de.opalstack.com to domains that use the Microsoft 365 email system.\u003c/p\u003e\n\u003cp\u003eMicrosoft\u0026rsquo;s own IP reputation and junk mail reporting systems indicate that there are no problems with smtp.de.opalstack.com so we\u0026rsquo;ve reached out to them for answers.\u003c/p\u003e\n\u003cp\u003eWe\u0026rsquo;ll update this post as soon as more information is available.\u003c/p\u003e\n\u003cp\u003eIn the interim as a possible workaround customers may create a new mailbox on our US mail server and use that temporarily for their outgoing email authentication. \n  \u003cspan class=\"faded\"\u003e(21:40 UTC — Jan 3)\u003c/span\u003e\n\n\u003c/p\u003e\n",
  "createdAt": "2022-01-03 21:40:00 +0000 UTC",
  "lastMod": "2022-01-03 21:40:00 +0000 UTC",
  "permalink": "https://opalstackstatus.com/issues/2022-01-03-german-smtp-blocked-by-microsoft/",
  "severity": "down",
  "resolved": true,
  "informational": false,
  "resolvedAt": "2022-01-17 15:04:53",
  "affected": ["SMTP (DE)"],
  "filename": "2022-01-03-german-smtp-blocked-by-microsoft.md"
}