T-Mobile Dash sync problems with Windows Mobile Device Center

Ok, i have a severe problem right now. i had sync'd all my contacts from my
t-mobile dash (htc s610) in windows mobile device center in windows vista
home premium edition before upgrading my device to windows mobile 6.0;now i'm
unable to sync my contacts from the previous partnership setup with the
device;under the sync center, it shows my previous device sync, but everytime
i connect my device, it appears as a guest and simply asks me to setup the
device with a new partnership profile. so how can i transfer my partnership
profile to the new one in order for it to update my contacts?