I came across this interesting question over on technet last week:

Hi,

Is there a way to restrict Mailbox owner from sending internal and external mails?
Are there any restrictive permissions which can be set on the user object in AD which will deny the user from sending any mails from his mailbox. The user should be able to receive and read the mails from the mailbox.

I have tried the option to set the sending limit of the user to 1 KB however i need to know if we can achieve this using permissions.

Mahendra

At first glance you may think that this is tricky to implement and requires messing around with permissions or server settings but as long as you are using Exchange 2007 or Exchange 2010 it is easy to implement (and more importantly, easy to manage!), and it is a great way to introduce how to work with Transport Rules.

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