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To Update permissions in bulk
69. Click on the checkboxes next to each username you wish to update.
10. Click the 
button, you should get a form window with a set of attributes / fields permissions you can update in bulk for that user:
7those users:
Note, this form (currently) does not indicate the current resultant boolean permission state for all users for each checkbox.
11. Update the desired attributes / fields.
To see a description of each permission, see how To create (add) a new user
812. Click Save OK to update or (or Cancel to cancel).
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To disable a user
913. Click on the specified username and you should get the Update user page.
1014. Click the Disable user button 
on the left. You should get another page asking for confirmation:
1115. Click Disable User to disable the user (or Cancel to cancel).
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To enable a user
1216. Click on the specified username and you should get the Update user page.
1317. Click the Enable user button 
on the left. You should get another page asking for confirmation and to set the new password:
1418. Type the new password then click Enable User to enable the user (or Cancel to cancel).
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To reset user passwords
1219. Click on the specified username and you should get the Update user page.
1320. Click on the Reset Password button 
You should get a another page with a prompt for the new password:
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Note, Reset Password is considered an admin-level operation that requires the USER_READ & USER_MODIFY permissions. This is distinct from the Change Password operation which does not require any permission and only applies to one's own password (see REST API for more details).
1421. In the New Password field, enter the new password.
1522. Click Submit to reset to the new password (or Cancel to cancel).