{"id":18295,"date":"2026-09-03T03:02:45","date_gmt":"2026-09-02T18:02:45","guid":{"rendered":"https:\/\/m365jp.net\/?p=18295"},"modified":"2026-09-03T03:05:19","modified_gmt":"2026-09-02T18:05:19","slug":"servicedegradation-ex1464935-exchange-online-users-may-be-unable-to-connect-to-or-experience-degraded-functionality-with-exchange-online-19","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-19","title":{"rendered":"[serviceDegradation] EX1464935 | Exchange Online | Users may be unable to connect to, or experience degraded functionality with Exchange Online"},"content":{"rendered":"<div class=\"postie-post\">\n<div>\n<hr>\n<table id=\"section\">\n<tbody>\n<tr>\n<th width=\"95%\">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<hr>\n<table id=\"data\">\n<tbody>\n<tr>\n<th>Status<\/th>\n<td class=\"bad\">serviceDegradation<\/td>\n<\/tr>\n<tr>\n<th>Classification<\/th>\n<td>incident<\/td>\n<\/tr>\n<tr>\n<th>User Impact<\/th>\n<td>Users may be unable to connect to, or experience degraded functionality with Exchange Online.<\/td>\n<\/tr>\n<tr>\n<th>Last Updated<\/th>\n<td>09\/02\/2026 17:26:01<\/td>\n<\/tr>\n<tr>\n<th>Start Time<\/th>\n<td>08\/31\/2026 15:08:00<\/td>\n<\/tr>\n<tr>\n<th>End Time<\/th>\n<td><\/td>\n<\/tr>\n<tr>\n<th>Latest Message<\/th>\n<td>Title: Users may be unable to connect to, or experience degraded functionality with Exchange Online<\/p>\n<p>  User impact: Users may be unable to connect to, or experience degraded functionality with Exchange Online.<\/p>\n<p>  More info: We&#8217;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<p>  We&#8217;ve opted to keep this post (EX1464935) open as Exchange Online remains the most predominantly impacted service.<\/p>\n<p>  Users may experience a variety of symptoms related to this event, including but not limited to:<br \/>  &#8211; Users can&#8217;t download email message attachments through any Exchange Online connection method.<br \/>  &#8211; Delays, failures, or incomplete results when searching for content within Exchange Online mailboxes.<br \/>  &#8211; Delays or failures when sending or receiving email messages.<br \/>  &#8211; Authentication-related errors when accessing Exchange Online services.<br \/>  &#8211; Difficulties accessing or performing actions within Exchange administration experiences.<br \/>  &#8211; Intermittent failures affecting mailbox operations and message delivery work<br \/>  &#8211; Delays or failures when sending or receiving email messages via Outlook for iOS and Android.<br \/>  &#8211; Users may be unable to use room finder in Outlook calendars.<br \/>  &#8211; Users may be unable to sign in to Outlook on the web.<\/p>\n<p>  Current status: We\u2019re working on additional mitigation measures for the portion of infrastructure which have not yet returned to healthy service levels after deployment of our primary remediation. Service availability remains above 99 percent and our monitoring   shows impact is resolved for the majority of users. We remain engaged and committed to fully resolving this issue for all users.<\/p>\n<p>  Scope of impact: Users attempting to perform any of the outlined impact scenarios may be affected by this event.<\/p>\n<p>  Start time: Monday, August 31, 2026, at 3:08 PM UTC<\/p>\n<p>  Preliminary root cause: An issue within a core authentication configuration used by multiple Microsoft 365 services is resulting in impact.<\/p>\n<p>  Next update by: Wednesday, September 2, 2026, at 6:30 PM UTC<\/td>\n<\/tr>\n<\/tbody>\n<\/table><\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>EX1464935 | Exchange Online | Users may be unable to connect to, or experience degraded functionality with Exc [&hellip;]<\/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-18295","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/18295","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=18295"}],"version-history":[{"count":0,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/posts\/18295\/revisions"}],"wp:attachment":[{"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/media?parent=18295"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/categories?post=18295"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/m365jp.net\/index.php\/wp-json\/wp\/v2\/tags?post=18295"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}