Please add more info about your setup - what Pi model/RetroPie version/etc - as asked in https://retropie.org.uk/forum/topic/3/read-this-first.

Well poop. The adapter DOESN'T support 5ghz. I guess it has been longer than I thought since my last update. Time to buy another Pi!

@ehindy Do you have samba enabled? That's what makes it pop up on your network. I rather use a client to transfer like winscp or flashfxp. If you wish to go that route, enable ssh in raspi-config and insert the pi's ip with port 22 and login/pass of pi/raspberry in client.