{"id":14596,"date":"2026-01-22T04:01:34","date_gmt":"2026-01-21T19:01:34","guid":{"rendered":"https:\/\/m365jp.net\/?p=14596"},"modified":"2026-01-22T04:06:08","modified_gmt":"2026-01-21T19:06:08","slug":"servicerestored-mo1220495-microsoft-365-suite-users-may-be-unable-to-access-microsoft-365-services","status":"publish","type":"post","link":"https:\/\/m365jp.net\/index.php\/2026-01-22-servicerestored-mo1220495-microsoft-365-suite-users-may-be-unable-to-access-microsoft-365-services","title":{"rendered":"[serviceRestored] MO1220495 | Microsoft 365 suite | Users may be unable to access Microsoft 365 services"},"content":{"rendered":"
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MO1220495 | Microsoft 365 suite | Users may be unable to access Microsoft 365 services<\/th>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n\n\n\n\n\n\n\n\n\n\n
Status<\/th>\nserviceRestored<\/td>\n<\/tr>\n
Classification<\/th>\nincident<\/td>\n<\/tr>\n
User Impact<\/th>\nUsers may have been unable to access Microsoft 365 services, including Teams and Outlook.<\/td>\n<\/tr>\n
Last Updated<\/th>\n01\/21\/2026 18:24:26<\/td>\n<\/tr>\n
Start Time<\/th>\n01\/21\/2026 16:45:09<\/td>\n<\/tr>\n
End Time<\/th>\n01\/21\/2026 17:10:00<\/td>\n<\/tr>\n
Latest Message<\/th>\nTitle: Users may be unable to access Microsoft 365 services<\/p>\n

User impact: Users may have been unable to access Microsoft 365 services, including Teams and Outlook.<\/p>\n

More info: As this issue was a result of a third-party ISP Autonomous System Number (ASN) routing configuration issue; the impact to Microsoft 365 services may have manifested in a multitude of ways. For example, some users may have been unable to access the services and portals altogether, whereas others may have seen impact more variable, such being intermittently unable to send or receive email.<\/p>\n

Final status: We’ve determined this issue was a result of a third-party ISP Autonomous System Number (ASN) routing configuration issue, and we’ve identified that the third-party has taken action to remediate the impact to downstream services, such as Microsoft 365, and we’ve confirmed the issue is no longer occurring.<\/p>\n

Scope of impact: Your organization was affected by this event, and any of your users hosted in North America may have been impacted.<\/p>\n

Start time: Wednesday, January 21, 2026, at 4:10 PM UTC<\/p>\n

End time: Wednesday, January 21, 2026, at 5:10 PM UTC<\/p>\n

Root cause: A third-party ISP ASN routing configuration issue caused impact to downstream services, such as Microsoft 365.<\/p>\n

Next steps:
– We’re carefully monitoring our managed service environment to ensure the issue doesn’t reoccur, and we’re reviewing our service resilience practices to identify any necessary improvements so we can reduce the downtime associated with these types of ISP-dependent issues in the future.<\/p>\n

This is the final update for the event.<\/td>\n<\/tr>\n

Machine Translation<\/th>\n\u30bf\u30a4\u30c8\u30eb:\u30e6\u30fc\u30b6\u30fc\u306fMicrosoft 365\u30b5\u30fc\u30d3\u30b9\u306b\u30a2\u30af\u30bb\u30b9\u3067\u304d\u306a\u3044\u5834\u5408\u304c\u3042\u308a\u307e\u3059<\/p>\n

\u30e6\u30fc\u30b6\u30fc\u3078\u306e\u5f71\u97ff:\u30e6\u30fc\u30b6\u30fc\u306fMicrosoft 365\u30b5\u30fc\u30d3\u30b9(Teams\u3084Outlook\u3092\u542b\u3080)\u306b\u30a2\u30af\u30bb\u30b9\u3067\u304d\u306a\u304b\u3063\u305f\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u8a73\u7d30:\u3053\u306e\u554f\u984c\u306f\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3ISP\u306e\u81ea\u5f8b\u30b7\u30b9\u30c6\u30e0\u756a\u53f7(ASN)\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u8a2d\u5b9a\u306e\u554f\u984c\u304c\u539f\u56e0\u3067\u3001Microsoft 365\u30b5\u30fc\u30d3\u30b9\u3078\u306e\u5f71\u97ff\u306f\u3001\u3055\u307e\u3056\u307e\u306a\u5f62\u3067\u73fe\u308c\u3066\u3044\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002\u4f8b\u3048\u3070\u3001\u4e00\u90e8\u306e\u30e6\u30fc\u30b6\u30fc\u306f\u30b5\u30fc\u30d3\u30b9\u3084\u30dd\u30fc\u30bf\u30eb\u306b\u5b8c\u5168\u306b\u30a2\u30af\u30bb\u30b9\u3067\u304d\u306a\u304f\u306a\u3063\u305f\u5834\u5408\u3082\u3042\u308c\u3070\u3001\u6642\u6298\u30e1\u30fc\u30eb\u306e\u9001\u53d7\u4fe1\u304c\u3067\u304d\u306a\u304f\u306a\u308b\u306a\u3069\u3001\u5f71\u97ff\u304c\u591a\u69d8\u306a\u5834\u5408\u3082\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u6700\u7d42\u72b6\u6cc1:\u3053\u306e\u554f\u984c\u306f\u7b2c\u4e09\u8005ISP\u306e\u81ea\u5f8b\u30b7\u30b9\u30c6\u30e0\u756a\u53f7(ASN)\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u8a2d\u5b9a\u306e\u554f\u984c\u306b\u3088\u308b\u3082\u306e\u3067\u3042\u308b\u3068\u5224\u65ad\u3057\u3001\u305d\u306e\u7b2c\u4e09\u8005\u304cMicrosoft 365\u306a\u3069\u306e\u4e0b\u6d41\u30b5\u30fc\u30d3\u30b9\u3078\u306e\u5f71\u97ff\u3092\u662f\u6b63\u3059\u308b\u305f\u3081\u306b\u63aa\u7f6e\u3092\u8b1b\u3058\u305f\u3053\u3068\u3092\u78ba\u8a8d\u3057\u3001\u554f\u984c\u306f\u3082\u306f\u3084\u767a\u751f\u3057\u3066\u3044\u306a\u3044\u3053\u3068\u3092\u78ba\u8a8d\u3057\u307e\u3057\u305f\u3002<\/p>\n

\u5f71\u97ff\u7bc4\u56f2:\u8cb4\u7d44\u7e54\u306f\u3053\u306e\u30a4\u30d9\u30f3\u30c8\u306e\u5f71\u97ff\u3092\u53d7\u3051\u3066\u304a\u308a\u3001\u5317\u7c73\u3067\u30db\u30b9\u30c8\u3055\u308c\u3066\u3044\u308b\u30e6\u30fc\u30b6\u30fc\u306e\u4e2d\u306b\u3082\u5f71\u97ff\u3092\u53d7\u3051\u305f\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u958b\u59cb\u6642\u9593:2026\u5e741\u670821\u65e5\u6c34\u66dc\u65e5 16:10 UTC<\/p>\n

\u7d42\u4e86\u6642\u523b:2026\u5e741\u670821\u65e5\u6c34\u66dc\u65e5 17:10 UTC<\/p>\n

\u6839\u672c\u539f\u56e0:\u30b5\u30fc\u30c9\u30d1\u30fc\u30c6\u30a3\u306eISP\u306eASN\u30eb\u30fc\u30c6\u30a3\u30f3\u30b0\u8a2d\u5b9a\u306e\u554f\u984c\u304c\u3001Microsoft 365\u306a\u3069\u306e\u4e0b\u6d41\u30b5\u30fc\u30d3\u30b9\u306b\u5f71\u97ff\u3092\u53ca\u307c\u3057\u307e\u3057\u305f\u3002<\/p>\n

\u6b21\u306e\u30b9\u30c6\u30c3\u30d7:
– \u554f\u984c\u306e\u518d\u767a\u3092\u9632\u3050\u305f\u3081\u306b\u30de\u30cd\u30fc\u30b8\u30c9\u30b5\u30fc\u30d3\u30b9\u74b0\u5883\u3092\u6ce8\u610f\u6df1\u304f\u76e3\u8996\u3057\u3066\u304a\u308a\u3001\u4eca\u5f8c\u3053\u306e\u3088\u3046\u306aISP\u4f9d\u5b58\u306e\u554f\u984c\u306b\u95a2\u9023\u3059\u308b\u30c0\u30a6\u30f3\u30bf\u30a4\u30e0\u3092\u524a\u6e1b\u3067\u304d\u308b\u3088\u3046\u3001\u30b5\u30fc\u30d3\u30b9\u30ec\u30b8\u30ea\u30a8\u30f3\u30b9\u5bfe\u7b56\u3092\u898b\u76f4\u3057\u3066\u5fc5\u8981\u306a\u6539\u5584\u70b9\u3092\u7279\u5b9a\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n

\u3053\u308c\u304c\u30a4\u30d9\u30f3\u30c8\u306e\u6700\u7d42\u30a2\u30c3\u30d7\u30c7\u30fc\u30c8\u3067\u3059\u3002<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

MO1220495 | Microsoft 365 suite | Users may be unable to access Microsoft 365 services Status serviceRestored […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-14596","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/14596","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/comments?post=14596"}],"version-history":[{"count":0,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/14596\/revisions"}],"wp:attachment":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/media?parent=14596"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/categories?post=14596"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/tags?post=14596"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}