Hi @ネパリ サンデャ,
Once I enable the setting it will continue after disabling it also
Once this setting is configured on Exchange side, the setting on Outlook (user) side would be set to "All Email and Events", which is a user-side setting.
Based on my test, unfortunately there is no other method to reverse this change other than having users re-configure it in Outlook. (select other options than "All Email and Events")
In addition, new members added to the team after "Send copies of group conversations and events to group members" was turned off would not be affected and would have the default setting "Only Replies to You and Events".
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