{"id":18305,"date":"2026-09-03T06:02:06","date_gmt":"2026-09-02T21:02:06","guid":{"rendered":"https:\/\/m365jp.net\/?p=18305"},"modified":"2026-09-03T06:02:35","modified_gmt":"2026-09-02T21:02:35","slug":"servicedegradation-ex1464935-exchange-online-users-may-be-unable-to-connect-to-or-experience-degraded-functionality-with-exchange-online-21","status":"publish","type":"post","link":"https:\/\/m365jp.net\/index.php\/2026-09-03-servicedegradation-ex1464935-exchange-online-users-may-be-unable-to-connect-to-or-experience-degraded-functionality-with-exchange-online-21","title":{"rendered":"[serviceDegradation] 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>\nserviceDegradation<\/td>\n<\/tr>\n
Classification<\/th>\nincident<\/td>\n<\/tr>\n
User Impact<\/th>\nUsers may be unable to connect to, or experience degraded functionality with Exchange Online.<\/td>\n<\/tr>\n
Last Updated<\/th>\n09\/02\/2026 20:31:46<\/td>\n<\/tr>\n
Start Time<\/th>\n08\/31\/2026 15:08:00<\/td>\n<\/tr>\n
End Time<\/th>\n<\/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 be unable to connect to, or experience degraded functionality with Exchange Online.<\/p>\n

More info: We’ve confirmed that the authentication component issue impacts 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 remains the most predominantly impacted service.<\/p>\n

Users may experience a variety of symptoms related to this event, including but not limited to:
– Users can’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 be unable to use room finder in Outlook calendars.
– Users may be unable to sign in to Outlook on the web.<\/p>\n

Current status: We\u2019ve completed a restart of affected Outlook on the web infrastructure, and service telemetry indicates that the majority of users have recovered. We\u2019re continuing to closely monitor service health as we roll out more durable fixes designed to address the underlying conditions contributing to the impact.<\/p>\n

In parallel, we\u2019re working directly with affected users and examining reports of continued impact to gather additional diagnostic information and identify any remaining issues. <\/p>\n

We remain focused on fully restoring service for all affected users and will continue deploying our fixes, investigating reports of impact, and monitoring service health until we\u2019re confident the issue is fully resolved.<\/p>\n

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

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

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

Next update by: Wednesday, September 2, 2026, at 10:30 PM UTC<\/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

\u30e6\u30fc\u30b6\u30fc\u3078\u306e\u5f71\u97ff:\u30e6\u30fc\u30b6\u30fc\u306fExchange Online\u306b\u63a5\u7d9a\u3067\u304d\u306a\u304f\u306a\u3063\u305f\u308a\u3001\u6a5f\u80fd\u306e\u4f4e\u4e0b\u3092\u611f\u3058\u308b\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u8a73\u7d30\u60c5\u5831:\u8a8d\u8a3c\u30b3\u30f3\u30dd\u30fc\u30cd\u30f3\u30c8\u306e\u554f\u984c\u306fExchange Online\u4ee5\u5916\u306e\u30b5\u30fc\u30d3\u30b9\u306b\u3082\u5f71\u97ff\u304c\u3042\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

Exchange Online\u304c\u6700\u3082\u5927\u304d\u306a\u5f71\u97ff\u3092\u53d7\u3051\u3066\u3044\u308b\u30b5\u30fc\u30d3\u30b9\u3067\u3042\u308b\u305f\u3081\u3001\u3053\u306e\u6295\u7a3f(EX1464935)\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\u3059\u308b\u3053\u3068\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\u3002
– Exchange Online\u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\u5185\u3067\u30b3\u30f3\u30c6\u30f3\u30c4\u3092\u691c\u7d22\u3059\u308b\u969b\u306e\u9045\u5ef6\u3001\u5931\u6557\u3001\u307e\u305f\u306f\u4e0d\u5b8c\u5168\u306a\u7d50\u679c\u3002
– \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
– \u30e1\u30fc\u30eb\u30dc\u30c3\u30af\u30b9\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
– 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\u306e\u30ab\u30ec\u30f3\u30c0\u30fc\u3067\u30eb\u30fc\u30e0\u30d5\u30a1\u30a4\u30f3\u30c0\u30fc\u3092\u4f7f\u3048\u306a\u3044\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002
– \u30e6\u30fc\u30b6\u30fc\u306f\u30a6\u30a7\u30d6\u4e0a\u306eOutlook\u306b\u30b5\u30a4\u30f3\u30a4\u30f3\u3067\u304d\u306a\u3044\u5834\u5408\u304c\u3042\u308a\u307e\u3059\u3002<\/p>\n

\u73fe\u72b6:\u5f71\u97ff\u3092\u53d7\u3051\u305fOutlook on the Web\u30a4\u30f3\u30d5\u30e9\u30b9\u30c8\u30e9\u30af\u30c1\u30e3\u306e\u518d\u8d77\u52d5\u3092\u5b8c\u4e86\u3057\u3001\u30b5\u30fc\u30d3\u30b9\u30c6\u30ec\u30e1\u30c8\u30ea\u3067\u306f\u5927\u591a\u6570\u306e\u30e6\u30fc\u30b6\u30fc\u304c\u56de\u5fa9\u3057\u305f\u3053\u3068\u304c\u793a\u3055\u308c\u3066\u3044\u307e\u3059\u3002\u5f71\u97ff\u306e\u6839\u672c\u7684\u306a\u539f\u56e0\u306b\u5bfe\u51e6\u3059\u308b\u305f\u3081\u306e\u3088\u308a\u6301\u7d9a\u7684\u306a\u4fee\u6b63\u3092\u5c55\u958b\u3057\u3064\u3064\u3001\u30b5\u30fc\u30d3\u30b9\u306e\u5065\u5168\u6027\u3092\u5f15\u304d\u7d9a\u304d\u6ce8\u8996\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n

\u540c\u6642\u306b\u3001\u5f71\u97ff\u3092\u53d7\u3051\u305f\u30e6\u30fc\u30b6\u30fc\u3068\u76f4\u63a5\u9023\u643a\u3057\u3001\u7d99\u7d9a\u7684\u306a\u5f71\u97ff\u306e\u5831\u544a\u3092\u691c\u8a3c\u3057\u3066\u8ffd\u52a0\u306e\u8a3a\u65ad\u60c5\u5831\u3092\u96c6\u3081\u3001\u6b8b\u308b\u554f\u984c\u3092\u7279\u5b9a\u3057\u3066\u3044\u307e\u3059\u3002 <\/p>\n

\u5f71\u97ff\u3092\u53d7\u3051\u305f\u3059\u3079\u3066\u306e\u30e6\u30fc\u30b6\u30fc\u306e\u30b5\u30fc\u30d3\u30b9\u3092\u5b8c\u5168\u306b\u5fa9\u65e7\u3059\u308b\u3053\u3068\u306b\u6ce8\u529b\u3057\u3001\u4fee\u6b63\u3092\u5c55\u958b\u3057\u3001\u5f71\u97ff\u5831\u544a\u306e\u8abf\u67fb\u3084\u30b5\u30fc\u30d3\u30b9\u306e\u5065\u5168\u6027\u3092\u76e3\u8996\u3057\u3001\u554f\u984c\u304c\u5b8c\u5168\u306b\u89e3\u6c7a\u3059\u308b\u307e\u3067\u7d9a\u3051\u307e\u3059\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\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

\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\u3066\u3044\u307e\u3059\u3002<\/p>\n

\u6b21\u56de\u66f4\u65b0:2026\u5e749\u67082\u65e5\u6c34\u66dc\u65e5 22:30 UTC<\/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-18305","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/18305","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=18305"}],"version-history":[{"count":0,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/18305\/revisions"}],"wp:attachment":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/media?parent=18305"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/categories?post=18305"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/tags?post=18305"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}