Windows Mobile 6 Standard (Smartphone) won't sync with Windows Vista
File synchronization with Windows Mobile 6 Standard devices is only supported by ActiveSync 4.5, not the new Windows Mobile Device Center (WMDC). As Vista users have to sync their smartphones with WMDC, they don't have access to this feature.
Microsoft’s statement:
Currently, Windows Mobile 6 users can synchronize files between PCs and smartphones with Active Sync 4.5. Microsoft will update Windows Mobile Device Center (WMDC) on Windows Vista PCs to support file synchronization with Windows Mobile 6 by mid-June. We appreciate our customers continuing to use ActiveSync 4.5 for file synchronization until this update is available and are looking forward to offering the WMDC synchronize option very soon.
However, ActiveSync 4.5 will not install on Windows Vista, so in a round about way, if you have a Windows Mobile 6 standard device (like an upgraded T-Mobile Dash), you won’t be able to sync with Windows Vista until the fix is available.