It could be that its still trying to pair via WiFi. Try these steps to sync via Bluetooth:
To sync via Bluetooth:
1. Launch the Setup Assistant (from your desktop) but choose the the Bluetooth pairing steps. Choose your Android device and enter a key of your choice on your desktop, also enter this in the notifications on your device. You are now paired via Bluetooth.
2. Open the Missing Sync settings on your phone again and look for the 'Bluetooth Sync' setting where you can select your desktop.
3. I would also enable 'diagnostics' in the MIssing Sync app on the phone. (dial “*#*#4114#*#*” from the phone application) Then go back to Missing Sync main window, click on the 'synchronize' bar and then you will see the diagnostic screen which shows the pairing. If you see the keypad, clear it (use back button) and look at the bottom for the 'sync bluetooth' button and click on it. You should be able to sync via Bluetooth.
Now try to sync and it will be syncing over Bluetooth