Hi I am Abdul Majid Khan, new to list and like to block attachments by extensions in Exchange 5.5? I can not find anything to block the incoming and outgoing emails attachments. I am on Exchange 5.5 with SP3. I am using Norton Anti Virus for Exchange 2.0, which also can not block the attachments. It is available after NAV 2.0. Please someone tell me any way of doing this, or any free software or Add on for Exchange 5.5. Thanks