ActiveSync 4.0

PocketPC

ActiveSync 4.0にして一番困るのがWi-Fi接続での接続が出来ない点です。クレードルは会社に置きっぱなしなので、今までは充電でもしながらWi-Fiで自宅PCと接続できたのが、いちいち出張鞄に入っているUSBケーブルを引っ張り出してこなくてはいけません。おかげで最近ではUSBケーブル出しっぱなしで、出張の時に忘れていきそう（カーソケット＋コンセントの充電用ケーブルになる）です。
青歯ならPCと接続出来るようなので、USBトグルでも買ってこようかな。でも今は金欠なので、無理です(^^;。

from Aximsite (Biboroku)
ActiveSync 4.0/4.1 do not support WiFi for security reason. On the other hand, X51v makes Bluetooth ActiveSync much easier with Windows XP SP2.

On your desktop, create a new incoming COM port for Bluetooth, i.e. Control Panel > Bluetooth Devices > COM Ports > Add... > Check Incoming > OK. Remember the new COM port number (e.g. COM20)

Open up ActiveSync on your desktop, and click File > Connection Settings > Check "Allow connections to one of the following" > Select the Bluetooth COM port you just created.

On your X51v, make sure you paired it with your desktop. Then go to Start > Settings > Connections > Bluetooth > Devices, click on your desktop and click Refresh button. Make sure the "ActiveSync" services is listed. If it's not listed, you may need to redo the steps above.

Open up ActiveSync on your X51v, click Menu > Connect via Bluetooth. It's done.

Bluetooth ActiveSync also support two desktop, simply click the "Connect via Bluetooth" and it'll discover if any desktop nearby.