There is a bug (imagine that, with a MS product) which is still being documented wherein the auto-sync between your Android mobile and Exchange server can result in the complete loss of your Outlook calendar and task list. It has happened to three folks at our office since the first of the year. We finally called in a MS Exchange 'expert' (i.e., he gets paid a lot more than I do) who concluded, "There is an apparent incompatibility issue."
After major buck$ and great consternation, the only solution that he (or the MS tech with whom our IT manager addressed the issue) was a 3rd party app called "Touch Down" for syncing your Android phone with Exchange. It's available via http://www.appbrain.com" onclick="window.open(this.href);return false; as a free version (somewhat limited and you cannot change the message at the footer of email or texts sent via the phone). After using it for a week I broke down and bought the full version.
So far so good...
