I coudn't browse with IE. I suspect Networking problem. How to test it?

Test your Networking issues in Safe Mode.

1. Restart the computer. Press the F8 key repeatedly when the screen goes blank.
2. Click Safe Mode with Networking, and press ENTER.
3. If you are presented with an option to select a version of Windows, select the appropriate version, and then press ENTER.
4. After the computer has started in safe mode, test your connection.

If you can connect internet when the computer is in safe mode, there is usually a third-party tool or program conflict. A clean restart may help you resolve the conflict. Restart the computer in normal mode and go to Step 1.

If you cannot connect to the Internet when the computer in safe mode, there may be a problem with the network adapter.