When you uninstall the adapter, make sure you are also uninstalling any drivers for it. Then reboot the laptop before you reinstall it and its drivers.
Then try this...
When WiFi won't connect.
First, make sure your laptop is 'not' connected to the modem/router via an Ethernet cable and follow the steps:
1. Go to "Control Panel".
2. Next go to "Network and Internet" and then "Network and Sharing".
3. Now click on "Manage Wireless Networks".
4. On this screen, remove all wireless connections by "right clicking" on it and select "Remove network" from the drop down menu.
5. After doing this, close the windows and scan for the "Wi-Fi networks".
6. Click on the available network that you want to access and select "connect".
7...