Hi all
I am running MS Exchange Server 5.5 in our Network. Actually the user can send email to un-limit of email addresses. So is there any way or tool to restrict the sending to specific number of recipients.
For example, the user can’t send one mail to more than 15 recipients.

1. Start Registry Editor (Reged32.exe).

2. Locate the following key in the registry:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\MSExchangeIS\ ParametersSystem

3. On the Edit menu, click Add Value, and then add the following registry value:

Value Name: Max Recipients on Submit

Data Type: REG_DWORD

String: A value equal to the maximum number of recipients that you want to allow

4. Quit Registry Editor.

In Exchange Server 5.5 and earlier, this limit also applies to messages that are transferred into the store by the Internet Mail Service. An event ID 4117 message is logged and the message is moved to the Archive folder. The message is not delivered and it does not send a non-delivery report (NDR).

Note the following when you add the above registry key:
• You do not have to stop and restart services for this change to take effect.
• The number you choose applies to total recipients associated with a message (To+Cc+Bcc=Total).
• You cannot circumvent the limit by using a personal distribution list; it is evaluated for number of entries before the send.
• Server-based distribution lists allow you to exceed the total number of recipients if you have proper permissions.

Oh good this is a good solution but will it apply for all users on the exchange. I don’t want this solution to be applied for the IT Administrator

That's why spammers are so successful, it's all or none. Sorry.

What do you mean of Spammers. Can you explain !

People who send out junk mail By the millions.