{"id":18350,"date":"2026-09-04T06:02:23","date_gmt":"2026-09-03T21:02:23","guid":{"rendered":"https:\/\/m365jp.net\/?p=18350"},"modified":"2026-09-04T06:04:17","modified_gmt":"2026-09-03T21:04:17","slug":"servicerestored-ex1464935-exchange-online-users-may-be-unable-to-connect-to-or-experience-degraded-functionality-with-exchange-online","status":"publish","type":"post","link":"https:\/\/m365jp.net\/index.php\/2026-09-04-servicerestored-ex1464935-exchange-online-users-may-be-unable-to-connect-to-or-experience-degraded-functionality-with-exchange-online","title":{"rendered":"[serviceRestored] EX1464935 | Exchange Online | Users may be unable to connect to, or experience degraded functionality with Exchange Online"},"content":{"rendered":"
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EX1464935 | Exchange Online | Users may be unable to connect to, or experience degraded functionality with Exchange Online<\/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 connect to, or experienced degraded functionality with Exchange Online.<\/td>\n<\/tr>\n
Last Updated<\/th>\n09\/03\/2026 20:29:03<\/td>\n<\/tr>\n
Start Time<\/th>\n08\/31\/2026 15:08:00<\/td>\n<\/tr>\n
End Time<\/th>\n09\/03\/2026 10:00:00<\/td>\n<\/tr>\n
Latest Message<\/th>\nTitle: Users may be unable to connect to, or experience degraded functionality with Exchange Online<\/p>\n

User impact: Users may have been unable to connect to, or experienced degraded functionality with Exchange Online.<\/p>\n

More info: We’ve confirmed that the authentication component issue impacted other services beyond Exchange Online. For more information regarding other impact scenarios, please see: MO1465074.<\/p>\n

We’ve opted to keep this post (EX1464935) open as Exchange Online was the most predominantly impacted service.<\/p>\n

Users may have experienced a variety of symptoms related to this event, including but not limited to:
– Users couldn’t download email message attachments through any Exchange Online connection method.
– Delays, failures, or incomplete results when searching for content within Exchange Online mailboxes.
– Delays or failures when sending or receiving email messages.
– Authentication-related errors when accessing Exchange Online services.
– Difficulties accessing or performing actions within Exchange administration experiences.
– Intermittent failures affecting mailbox operations and message delivery work.
– Delays or failures when sending or receiving email messages via Outlook for iOS and Android.
– Users may have been unable to use room finder in Outlook calendars.
– Users may have been unable to sign in to Outlook on the web.<\/p>\n

Final status: Based on our telemetry all previously impacted services have remained healthy since impact was remediated on Thursday, September 3, 2026, at 10:00 AM UTC, and this issue is resolved.<\/p>\n

Scope of impact: Users attempting to perform any of the outlined impact scenarios may have been affected by this event.<\/p>\n

Start time: Monday, August 31, 2026, at 3:08 PM UTC<\/p>\n

End time: Thursday, September 3, 2026, at 10:00 AM UTC<\/p>\n

Preliminary root cause: An issue within a core authentication configuration used by multiple Microsoft 365 services was resulting in impact.<\/p>\n

Next steps:
– We\u2019re evaluating our core authentication configurations to prevent the recurrence of similar impact in the future. In addition, we’re further reviewing our monitoring systems to ensure we identify and are expediently alerted to these types of scenarios.<\/p>\n

We’ll provide a preliminary Post-Incident Report within two business days and a final Post-Incident Report within five business days.<\/td>\n<\/tr>\n

Machine Translation<\/th>\n\u30bf\u30a4\u30c8\u30eb:\u30e6\u30fc\u30b6\u30fc\u304cExchange Online\u306b\u63a5\u7d9a\u3067\u304d\u306a\u304f\u306a\u3063\u305f\u308a\u3001\u6a5f\u80fd\u304c\u52a3\u5316\u3057\u3066\u3044\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059<\/p>\n

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\u8a73\u7d30\u60c5\u5831:\u8a8d\u8a3c\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u306e\u554f\u984c\u304cExchange Online\u4ee5\u5916\u306e\u30b5\u30fc\u30d3\u30b9\u306b\u3082\u5f71\u97ff\u3092\u53ca\u307c\u3057\u3066\u3044\u308b\u3053\u3068\u3092\u78ba\u8a8d\u3057\u307e\u3057\u305f\u3002\u305d\u306e\u4ed6\u306e\u5f71\u97ff\u30b7\u30ca\u30ea\u30aa\u306b\u3064\u3044\u3066\u306f\u3001MO1465074\u3092\u3054\u89a7\u304f\u3060\u3055\u3044\u3002<\/p>\n

\u3053\u306e\u6295\u7a3f(EX1464935)\u306f\u3001Exchange Online\u304c\u6700\u3082\u5927\u304d\u306a\u5f71\u97ff\u3092\u53d7\u3051\u305f\u30b5\u30fc\u30d3\u30b9\u3060\u3063\u305f\u305f\u3081\u3001\u3053\u306e\u6295\u7a3f\u306f\u958b\u3044\u305f\u307e\u307e\u306b\u3059\u308b\u3053\u3068\u306b\u3057\u307e\u3057\u305f\u3002<\/p>\n

\u5229\u7528\u8005\u306f\u3053\u306e\u51fa\u6765\u4e8b\u306b\u95a2\u9023\u3059\u308b\u3055\u307e\u3056\u307e\u306a\u75c7\u72b6\u3092\u7d4c\u9a13\u3057\u305f\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u304c\u3001\u4ee5\u4e0b\u306b\u9650\u5b9a\u3055\u308c\u307e\u305b\u3093\u3002
– \u30e6\u30fc\u30b6\u30fc\u306fExchange Online\u306e\u63a5\u7d9a\u65b9\u6cd5\u3092\u901a\u3058\u3066\u30e1\u30fc\u30eb\u6dfb\u4ed8\u30d5\u30a1\u30a4\u30eb\u3092\u30c0\u30a6\u30f3\u30ed\u30fc\u30c9\u3067\u304d\u307e\u305b\u3093\u3067\u3057\u305f\u3002
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– \u30e1\u30fc\u30eb\u306e\u9001\u53d7\u4fe1\u306b\u304a\u3051\u308b\u9045\u5ef6\u3084\u5931\u6557\u3002
– Exchange Online\u30b5\u30fc\u30d3\u30b9\u3078\u306e\u30a2\u30af\u30bb\u30b9\u6642\u306e\u8a8d\u8a3c\u95a2\u9023\u30a8\u30e9\u30fc\u3002
– \u53d6\u5f15\u6240\u7ba1\u7406\u4f53\u9a13\u5185\u3067\u306e\u64cd\u4f5c\u3084\u30a2\u30af\u30bb\u30b9\u306e\u56f0\u96e3\u3002
– \u90f5\u4fbf\u53d7\u3051\u64cd\u4f5c\u3084\u30e1\u30c3\u30bb\u30fc\u30b8\u914d\u4fe1\u4f5c\u696d\u306b\u5f71\u97ff\u3092\u4e0e\u3048\u308b\u65ad\u7d9a\u7684\u306a\u969c\u5bb3\u3002
– Outlook(iOS\u304a\u3088\u3073Android)\u3067\u306e\u30e1\u30fc\u30eb\u9001\u53d7\u4fe1\u306e\u9045\u5ef6\u3084\u5931\u6557\u3002
– \u30e6\u30fc\u30b6\u30fc\u306fOutlook\u30ab\u30ec\u30f3\u30c0\u30fc\u3067\u30eb\u30fc\u30e0\u30d5\u30a1\u30a4\u30f3\u30c0\u30fc\u3092\u4f7f\u3048\u306a\u304b\u3063\u305f\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002
– \u30e6\u30fc\u30b6\u30fc\u304c\u30a6\u30a7\u30d6\u4e0a\u3067Outlook\u306b\u30b5\u30a4\u30f3\u30a4\u30f3\u3067\u304d\u306a\u304b\u3063\u305f\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u6700\u7d42\u72b6\u6cc1:\u5f53\u793e\u306e\u30c6\u30ec\u30e1\u30c8\u30ea\u306b\u57fa\u3065\u304d\u30012026\u5e749\u67083\u65e5\u6728\u66dc\u65e5\u5348\u524d10\u6642(UTC)\u306b\u5f71\u97ff\u304c\u4fee\u5fa9\u3055\u308c\u3066\u4ee5\u6765\u3001\u3053\u308c\u307e\u3067\u5f71\u97ff\u3092\u53d7\u3051\u305f\u3059\u3079\u3066\u306e\u30b5\u30fc\u30d3\u30b9\u306f\u5065\u5eb7\u3092\u7dad\u6301\u3057\u3066\u304a\u308a\u3001\u3053\u306e\u554f\u984c\u306f\u89e3\u6c7a\u3055\u308c\u307e\u3057\u305f\u3002<\/p>\n

\u5f71\u97ff\u7bc4\u56f2:\u4e0a\u8a18\u306e\u5f71\u97ff\u30b7\u30ca\u30ea\u30aa\u306e\u3044\u305a\u308c\u304b\u3092\u5b9f\u884c\u3057\u3088\u3046\u3068\u3059\u308b\u30e6\u30fc\u30b6\u30fc\u306f\u3001\u3053\u306e\u30a4\u30d9\u30f3\u30c8\u306e\u5f71\u97ff\u3092\u53d7\u3051\u3066\u3044\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u958b\u59cb\u6642\u9593:2026\u5e748\u670831\u65e5(\u6708)\u5348\u5f8c3\u664208\u5206(UTC)<\/p>\n

\u7d42\u4e86\u6642\u523b:2026\u5e749\u67083\u65e5\u6728\u66dc\u65e5 \u5348\u524d10\u6642 UTC<\/p>\n

\u4e88\u5099\u7684\u306a\u6839\u672c\u539f\u56e0:\u8907\u6570\u306eMicrosoft 365\u30b5\u30fc\u30d3\u30b9\u3067\u4f7f\u7528\u3055\u308c\u308b\u30b3\u30a2\u8a8d\u8a3c\u69cb\u6210\u306e\u554f\u984c\u304c\u5f71\u97ff\u3092\u53ca\u307c\u3057\u307e\u3057\u305f\u3002<\/p>\n

\u6b21\u306e\u30b9\u30c6\u30c3\u30d7:
– \u4eca\u5f8c\u540c\u69d8\u306e\u5f71\u97ff\u304c\u518d\u767a\u3057\u306a\u3044\u3088\u3046\u306b\u3001\u30b3\u30a2\u8a8d\u8a3c\u8a2d\u5b9a\u3092\u8a55\u4fa1\u3057\u3066\u3044\u307e\u3059\u3002\u3055\u3089\u306b\u3001\u76e3\u8996\u30b7\u30b9\u30c6\u30e0\u306e\u518d\u78ba\u8a8d\u3092\u884c\u3044\u3001\u3053\u308c\u3089\u306e\u30b7\u30ca\u30ea\u30aa\u3092\u7279\u5b9a\u3057\u8fc5\u901f\u306b\u30a2\u30e9\u30fc\u30c8\u3067\u304d\u308b\u3088\u3046\u52aa\u3081\u3066\u3044\u307e\u3059\u3002<\/p>\n

\u4e88\u5099\u7684\u306a\u4e8b\u5f8c\u5831\u544a\u66f8\u30922\u55b6\u696d\u65e5\u4ee5\u5185\u306b\u3001\u6700\u7d42\u7684\u306a\u4e8b\u5f8c\u5831\u544a\u66f8\u30925\u55b6\u696d\u65e5\u4ee5\u5185\u306b\u63d0\u4f9b\u3057\u307e\u3059\u3002<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

EX1464935 | Exchange Online | Users may be unable to connect to, or experience degraded functionality with Exc […]<\/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-18350","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/18350","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=18350"}],"version-history":[{"count":0,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/18350\/revisions"}],"wp:attachment":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/media?parent=18350"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/categories?post=18350"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/tags?post=18350"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}