Is this a Wifi Adapter that WE provided?
Has the customer installed the Wifi drivers with the provided driver disc?
Have the customer install the drivers from the included disc, and refer to the alternate answer to this tree if issues arise..
Have the customer move the Wifi adapter to another USB slot, and note the message displayed in the bottom right corner of the screen. What did the notification read?
"Installing device driver software..." or "Device is ready to use". No response. "Device not recognized".
Connect to the wireless network as per usual..
Re-install drivers from the driver CD, Restart the PC, and re-insert the Wifi Adapter..
Test the USB port with a keyboard or mouse, is it working?
The Wifi Adapter may be faulty, offer to send a replacement..
The USB port is likely dead. This PC will need a repair, or at the minimum we'll need to use a different port for the adapter..
Has the customer installed the drivers from the CD included with this adapter?
Are wireless networks visible in the network list?
The customer will need to know their Wifi password, which can be obtained from the ISP / Network administrator..
Verify the adapter supports Windows 10, download and install drivers via another pc & flash drive, or advise to purchase another adapter that supports Windows 10..
Do they HAVE the installation disc for this adapter?
They will need to acquire drives for Windows 10 for this adapter from the manufacturer's website, or purchase a new adapter..
Install the drivers via the disc, and have them attempt to connect & browse. Did it work?
You win the Internet!.
They will likely need to purchase a new adapter, or acquire drivers for Windows 10 from the adapter's website..