This guide shows you how to enable or disable features on a mailbox:
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- Open up the Exchange Management Console.
- Expand Recipient Configuration.
- Click Mailbox.
- On the right hand side double click the mailbox you want to modify.
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- Step 1 -> Right click on the user account.
- Step 2 -> Click on Properties.
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- Step 1 -> Click on the Mailbox Features Tab.
- Step 2 -> you can enable/disable features as you need for a user.
- Once done click the ok button.
Hope it helps.