Wireless adapter not showing up on Windows.
Option 1... Enable Wireless Radio
Check that the wireless radio wasn't accidentally disabled. Most laptops have hard (or soft) buttons to turn on/off the wireless. Check your computers manual (If you weren't given one, check online for one), to find out which buttons are used for this.
Also, you should be able to turn on the wireless settings in BIOS. Restart your laptop and enter BIOS. In BIOS look for the "Network Settings" page. In there enable wireless radio or wireless devices (depending on how it is worded). Now click "Save" and then "Exit".
NOTE: Do be care while in BIOS and don't make any other changes.
Option 2... Fix Wireless Adapter Driver Issues
Wireless driver issues can be the driver is currupt, it is outdated, it is actually missing (was deleted) or it is incompatible with your hardware. There are programs out ther like "OSToto Driver Talent" the can fix the wireless driver issues. That particular program is free, and can check the computer and detect any driver issues. Once it is done, you can "Repair" or "Update" the drivers.
NOTE: Once this is done, and the program is finished, be sure you reboot the laptop.
Driver issues cause most of the hardware problems. And the wireless driver issues include driver
Option 3... Update Router and Adapter Firmware
The firmware could also be outdated. Old firmware can prevent the router/modem from accessing the Internet and effect any/all wireless devices. Be sure you check to see if there are updates to your hardwares firmware.
Option 4... Do a System Restore
If the driver seems to be just gone, or none of the former work, then you may want to try a "System Restore". This will allow you to 'restore' the system back to a date before the problem started. To do this type "System Restore" in the search box. Next choose the "Restore Point" that is dated 'before' the wireless problem started. When prompted, confirm the restore point and then let it do the restore. It can take a little while, so be patient.
Option 5... Add a USB Wireless Adapter
If nothing here has worked, you may need to buy and install a new adapter.