I am using HP15-R033tx laptop which has Ralink RT3290 wifi+bluetooth combo adapter.I read the forums online that the latest updates of windows 8.1 carry this problem with them. I contacted hp and they even replaced the adapter. So the adapter is brand new and error free. 

Please Help. I cannot connect my laptop using the ethernet cable forever. 

Hi BishwaBikash Das,

Did the machine connect to the Wifi successfully before? Could the other devices connect to the router?

For the specific model adapter, I found a specific update may result in some issues with this network adapter. Here is a link for reference:
Ralink Bluetooth PCIe Adapter for Windows 8.1 missing
http://h30434.www3.hp.com/t5/Wireless-Internet-Home-Networking/Ralink-Mediatek-Bluetooth-PCIe-Adapter-for-Windows-8-1/td-p/3242531/page/3

Please run "wusa /uninstall /KB:2887595" to verify whether this KB has been installed. If it has been installed ,please uninstall it and reinstall the network adapter driver again to have a check. It is recommended to download the latest driver for the device from the HP website.

If the issue persists, please take the following steps to have a troubleshoot:
1. Run the built-in troubleshoot to have a diagnostic.
Control Panel\All Control Panel Items\Troubleshooting\All Categories\Network Adapter
2. Refer to the following link to reset the TCP/IP stack
How to reset TCP/IP by using the NetShell utility
https://support.microsoft.com/en-us/kb/299357

If the issue persists, please check the Event Viewer for any error or warning messages to troubleshoot this issue.
Event Viewer\Applications and Services\Microsoft\Windows\Wlan-AutoConfig
Event Viewer\Windows Logs\Application, System

Best regards