I was having this same issue, and I am the IT Manager. After trying many things, I discovered I needed to add another virtual directory by exporting the Exchange one after disabling SSL and FBA. The link with step by step to do this process I found here:
http://support.microsoft.com/Default.aspx?kbid=817379
This totally solved my problem but I have to have SSL turned off in VersaMail. Anyway, it now syncs just fine, it transferred contacts, schedule, and emails. However, here is what I found odd. It is only downloading the last 4 days worth of emails or so. Hardly any. Anyone have any idea why I can't get it to sync my whole inbox? Anyone else run into this? If this is all it will do, then it is better than nothing, however I'd love to have more of my emails than that. Also, I'm using Mergic VPN to setup my VPN to do this activesync. I'm on a trial that is going to expire. Is there any free VPN palm software out there before I end up purchasing Mergic?
Thanks!