If I'm right you're trying to connect XL with PC...this is the way I'm using....
C/P
To pair your device wirelessly with a computer using Media transfer mode
Make sure Media transfer mode is enabled on your device. It is normally enabled by default.
Connect your device to the computer using a USB cable.
Computer: Once the name of your device appears on the screen, click Network configuration and follow the instructions to pair the computer.
When you are finished pairing, disconnect the USB cable from both devices.
The above instructions only work if Windows® 7 is installed on your computer and the computer is connected to a Wi-Fi® Access Point via a network cable.
To connect paired devices wirelessly in Media transfer mode
Make sure Media transfer mode is enabled on your device. It is normally enabled by default.
From your Home screen, tap Application screen icon in Sony Smartphones.
Find and tap Settings > Xperia™ > USB Connectivity.
Tap the paired device that you want to connect to under Trusted devices.
Tap Connect.
Make sure the Wi-Fi® function is turned on.
To disconnect a wirelessly paired device in Media transfer mode
From your Home screen, tap Application screen icon in Sony Smartphones.
Find and tap Settings > Xperia™ > USB Connectivity.
Tap the paired device that you want to disconnect from under Trusted devices.
Tap Disconnect.
To remove a pairing with another device
From your Home screen, tap Application screen icon in Sony Smartphones.
Find and tap Settings > Xperia™ > USB Connectivity.
Tap the paired device that you want to remove.
Tap Forget.