My settings in Zoom were changed without my knowledge.

Hi @jigenji thank you for your post here on the Zoom Community! If you are part of a larger organization, this setting could have been changed at the Account or Group level in which case it would impact your personal Zoom settings. Notice this image taken from the setting at the Account level

If I change this setting it changes defaults for users. And if I lock it, all users will have this setting applied. 

Zoom settings can be globally set at the account level. You also have user groups that can be created to define specific settings for different groups of users. Anything locked at the account level will be locked in the group level, too.

User settings are what you see when you first sign into the Zoom portal, in the upper left "Personal" section

Depending on what is set at the Account and/or Group level, you could notice your settings change at the personal level. 

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