Are you running through some secondary VPN by any chance. Is it set for 2.4ghz and 5ghz.
not really. have virus main wireless and a netgear repeater in the house 300' away; SSID's virus_2g & virus_5g... same pw...
just powered up old lynksys open wireless router on bench... set to WPA personal (and tried WPA2 personal) with simple psk="this_is-mine" and SSID="linked" same submask as my 'real' dsl modem, just different IP (0.103) and let it assign DHCP from (0.104 to 0.115) so I can see if it assigns anything... My workshop comput connects as .0.104, goes to the internet fine (I set my workshop for 0.1 router).
new wpa. no connection...
downloading from 2 different locations, 2 different names new:
raspbian 2018-06-27 stretch-lite.zip (from raspbian.org)
&
Raspbian 2018-06-27 2GB Stretch Lite (rpi3) (kernel 4.9).img.7z
will try first then second tomorrow...