Screwy Calendar Behavior!!

I have the same issue with my TP2. I am using XP and Outlook 2007. Anyone please help. Sprints Tech were useless, there only solution was to hard reset the phone. I told them I had already done that, but because they are the techs insisted that when they reset it the same way i did. It will fix the problem because they did it. I have exported all my contacts to my email server then dumped everything off my outlook and hard reset the phone. started fresh with both, and problem still shows up.