Suddenly, your laptop fails to connect to WiFi and replaces normal WiFi icon in its system tray (in bottom right corner of your screen) with a red-X-wireless-icon. This article definitely helps you out.
– Step 1: The very first thing you need to do is to check if wireless driver was installed properly. In the case of no wireless driver installed, your WiFi icon definitely has an exclamation mark on it. Press Start button, enter Device Manager in searching field and Enter.
Still lack drivers? Refer Websites for downloading drivers for all kind of computers
– Step 2: Press Start button again, enter Network and Sharing Center, and select Change adapter settings
– Step 3: Right click on Local Area Connection icon and select Enable
Still no WiFi connection? Go check if WiFi indicator on your laptop lighted on. It lights off means you turned it off. Press Fn + F2 key combination or other WiFi switch on laptop to turn it on.