I am running Squid 2.6 Stable 5 as a transparent proxy on my LAN, and all my clients pass through to another subnet where our Exchange server sits. Ever since I put the proxy in place my clients sporadically get messages in Outlook saying the their connection to the Exchange server is unavailable. It only lasts for about 3-4 seconds. Are there any specific ACLs I should be putting in my conf file to prevent this from happening? Or is it more likely a TPROXY issue? Thanks, Jared