Cannot Send/reply/forward In Outlook 2007

Hello All,

So here's my problem. I have just completed a rollout of Office 2007 at a client. One of the big-wigs is having an issue. He receives emails and can read them and their attachments. But if he attempts to forward or reply to the email Outlook stops responding and must be restarted. The same goes for creating and sending new emails as well. I can't even save a new email as a draft without the whole program crashing. Here is what I have tried. Removing add-ins, disabling security (ESET's NOD32 by the way)even an uninstall/reinstall. For some reason if I start Outlook in safe mode it will work, but that is merely a "band-aid" solution. Please help.

Oh, this is an XP Pro machine w/ Intel Core Duo 1.7GHz CPU and 2GB of RAM in an SBS 2003 environment with Outlook working through Exchange. Thanks.