I have a brand new htc HD2. I downloaded and installed Active Sync 4.5. After connecting the phone to the computer using the USB cable, the sync process proceeded with no errors. When I opened Mobile Outlook only about half of my appointments transfered (e.g. of six appointments for today in Outlook only three made it onto my phone; of three appointments for Saturday zero appointments made it on to the phone etc.) All of my other Outlook data (Contacts, Tasks, Email, and Notes) synchronized OK.