{"id":18446,"date":"2026-09-10T08:05:30","date_gmt":"2026-09-09T23:05:30","guid":{"rendered":"https:\/\/m365jp.net\/?p=18446"},"modified":"2026-09-10T08:14:41","modified_gmt":"2026-09-09T23:14:41","slug":"mc1469960-microsoft-exchange-online-review-and-configure-ewsallowedappids-before-exchange-web-services-access-changes","status":"publish","type":"post","link":"https:\/\/m365jp.net\/index.php\/2026-09-10-mc1469960-microsoft-exchange-online-review-and-configure-ewsallowedappids-before-exchange-web-services-access-changes","title":{"rendered":"MC1469960 | Microsoft Exchange Online: Review and configure EWSAllowedAppIDs before Exchange Web Services access changes"},"content":{"rendered":"
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MC1469960 | Microsoft Exchange Online: Review and configure EWSAllowedAppIDs before Exchange Web Services access changes<\/th>\n<\/tr>\n<\/tbody>\n<\/table>\n
\n\n\n\n\n\n\n\n\n
Classification<\/th>\npreventOrFixIssue<\/td>\n<\/tr>\n
Last Updated<\/th>\n09\/09\/2026 22:30:27<\/td>\n<\/tr>\n
Start Time<\/th>\n09\/09\/2026 22:30:08<\/td>\n<\/tr>\n
End Time<\/th>\n07\/30\/2027 07:00:00<\/td>\n<\/tr>\n
Message Content<\/th>\n\n

[What and why]<\/b><\/p>\n

As part of the final phase of Exchange Web Services (EWS) retirement, Microsoft is updating how the EWSAllowedAppIDs<\/b> setting is applied in Exchange Online<\/em>. This change is designed to help organizations identify and manage applications that still require EWS access while reducing the risk of unexpected service disruption.<\/p>\n

Organizations that continue to use EWS should review and maintain their own EWSAllowedAppIDs<\/b> list. If a tenant administrator has already configured this list, Microsoft will not overwrite or modify it.<\/p>\n

Beginning on October 1, 2026<\/b>, Microsoft will start enabling this updated behavior by cloud as part of the EWS retirement rollout.<\/p>\n

[Rollout schedule]<\/b><\/p>\n

    \n
  • Worldwide, GCC, GCC High, DoD:<\/b> Beginning in early October 2026<\/b> and expected to complete by late June 2027<\/b><\/li>\n<\/ul>\n

    The updated behavior will apply when the rollout reaches your cloud.<\/p>\n

    [Impact on your organization]<\/b><\/p>\n

    Who is affected<\/em><\/p>\n

      \n
    • Organizations that continue to use Exchange Web Services (EWS)<\/li>\n
    • Exchange Online administrators responsible for managing EWS access<\/li>\n
    • Tenants with EWSEnabled set to True or Null<\/li>\n<\/ul>\n

      Platforms and services<\/em><\/p>\n

        \n
      • Exchange Online<\/li>\n
      • Exchange Web Services (EWS)<\/li>\n<\/ul>\n

        What will happen<\/em><\/p>\n

        After the updated behavior is enabled in a cloud:<\/p>\n

          \n
        • EWS will require a configured EWSAllowedAppIDs<\/b> list when EWSEnabled<\/b> is set to True<\/b>.<\/li>\n
        • Before enabling the change, Microsoft will ensure that tenants with EWSEnabled <\/b>already set to True<\/b> have an EWSAllowedAppIDs<\/b> list.<\/li>\n
        • If a customer-managed list does not exist, Microsoft will generate a list based on EWS application usage observed during the previous 60 days to help reduce the risk of service interruption.<\/li>\n
        • Microsoft-generated lists may omit applications that run infrequently and may include applications that no longer require EWS access.<\/li>\n
        • If EWSEnabled<\/b> remains Null<\/b>, Microsoft will populate EWSAllowedAppIDs<\/b> only when a customer-managed list does not already exist. This will occur shortly before Microsoft updates EWSEnabled<\/b> to False as part of the retirement rollout.<\/li>\n
        • Microsoft will not modify an EWSAllowedAppIDs<\/b> list that has already been configured by a tenant administrator.<\/li>\n<\/ul>\n

          [Action required and recommendations]<\/b><\/p>\n

          If your organization still relies on EWS, we recommend taking the following actions as soon as possible:<\/p>\n

Machine Translation<\/th>\n\n

[\u4f55\u3068\u306a\u305c]<\/b><\/p>\n

Exchange Web Services(EWS)\u306e\u6700\u7d42\u6bb5\u968e\u306e\u4e00\u74b0\u3068\u3057\u3066\u3001Microsoft\u306fExchange Online<\/em>\u306b\u304a\u3051\u308bEWSAllowedAppIDs<\/b>\u8a2d\u5b9a\u306e\u9069\u7528\u65b9\u6cd5\u3092\u66f4\u65b0\u3057\u3066\u3044\u307e\u3059\u3002\u3053\u306e\u5909\u66f4\u306f\u3001\u7d44\u7e54\u304c\u4f9d\u7136\u3068\u3057\u3066EWS\u30a2\u30af\u30bb\u30b9\u3092\u5fc5\u8981\u3068\u3059\u308b\u30a2\u30d7\u30ea\u30b1\u30fc\u30b7\u30e7\u30f3\u3092\u7279\u5b9a\u3057\u7ba1\u7406\u3057\u3064\u3064\u3001\u4e88\u671f\u305b\u306c\u30b5\u30fc\u30d3\u30b9\u4e2d\u65ad\u306e\u30ea\u30b9\u30af\u3092\u6e1b\u3089\u3059\u3053\u3068\u3092\u76ee\u7684\u3068\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n

EWS\u3092\u5f15\u304d\u7d9a\u304d\u4f7f\u7528\u3059\u308b\u7d44\u7e54\u306f\u3001\u81ea\u793e\u306e EWSAllowedAppIDs<\/b> \u30ea\u30b9\u30c8\u3092\u30ec\u30d3\u30e5\u30fc\u3057\u3001\u7ba1\u7406\u3059\u3079\u304d\u3067\u3059\u3002\u30c6\u30ca\u30f3\u30c8\u7ba1\u7406\u8005\u304c\u3059\u3067\u306b\u3053\u306e\u30ea\u30b9\u30c8\u3092\u8a2d\u5b9a\u3057\u3066\u3044\u308b\u5834\u5408\u3001Microsoft\u306f\u305d\u308c\u3092\u4e0a\u66f8\u304d\u307e\u305f\u306f\u4fee\u6b63\u3057\u307e\u305b\u3093\u3002<\/p>\n

2026\u5e7410\u67081<\/b>\u65e5\u304b\u3089\u3001Microsoft\u306fEWS\u306e\u5b9a\u5e74\u9000\u8077\u62e1\u5927\u306e\u4e00\u74b0\u3068\u3057\u3066\u3001\u3053\u306e\u66f4\u65b0\u3055\u308c\u305f\u30af\u30e9\u30a6\u30c9\u52d5\u4f5c\u306e\u6709\u52b9\u5316\u3092\u958b\u59cb\u3057\u307e\u3059\u3002<\/p>\n

[\u5c55\u958b\u30b9\u30b1\u30b8\u30e5\u30fc\u30eb]<\/b><\/p>\n