I'm definitely not sure if it is the right forum or not I have a lot of users who use Outlook anywhere, and some of them do not connect on a daily basis and then sometimes kills my bandwidth during their mailboxes update. I would like to know who is killing my bandwidth? Of course on my firewall I can find out what IP addresses are connected to my exchange with https, but how can I find out the name of the user/mailbox being synchronized ?

Doing so live isn't going to be easy. However as it is all IIS, finding it through IIS logs should be pretty easy. There are many IIS log analysis tools available. I have used SmarterStats free version before with Exchange and it works pretty well. That should give you bandwidth reports. Simon.Simon Butler, Exchange MVP. http://blog.sembee.co.uk , http://exbpa.com/

I'll give it a try, but is it going to tell me who is updating his mailbox ?

All it may tell you is who is using the most bandwidth. Nothing more. You probably have a user who isn't using cached mode, and is therefore using Outlook live. That will kill bandwidth very quickly. Simon.Simon Butler, Exchange MVP Blog | Exchange Resources