Hi MANOHAR BHATIA,
The “Device Instance ID” that you have provided is for “Dell Wireless WLAN 1704 Half Mini-Card + BlueTooth 4.0”. There is a possibility your Ethernet Adapter is not enabled in the BIOS Setup. Please ensure under the "Advanced" tab in the BIOS Setup “Integrated NIC” is enabled . Check the image below for details:
If “Integrated NIC” is disabled in the BIOS Setup, enable it and check in the Device Manager if “Realtek RTL8111E-VB Gigabit Ethernet Controller” is detected.
Do reply with results.