Windows 10: Laptop disconnecting from wifi, only when "extender" is connected

I have one laptop (HP) that won't stay connected to wifi. It worked yesterday until I installed a new router/modem. All other devices unaffected. Here's my new setup:
New Arris SBG7400AC2 router/modem connected by coax. 2.4 and 5 have channel auto. SSIDs: Work, Work5G
DHCP range: 192.168.0.2-192.168.0.249
IP (gateway): 192.168.0.1 255.255.255.0

Older Netgear C6300 connected to Arris (wired). Turned off Use Gateway as DHCP Server
2.4 channel is auto and 5 is set to 157. SSIDs: Amp, Amp.5G
IP: 192.168.0.250 255.255.255.0

HP IP currently 192.168.0.4 (obtained auto)

With all equipment, I can ping both IPs successfully. With HP, I can ping .250 successfully, every time. I fail 3or4 out of 4 times (request timed out) when pinging .1, with HP.

I was thinking, must be internal NIC or settings on HP. So, I tried ipconfig release, renew, flushdns, various netsh commands (i i r r, winsock reset, etc.), making sure computer can't power down wifi, made sure on private network, forget network, turned on connect automatically (to each SSID individually, one at a time), lowered roam to Medium-low (so wifi wouldn't try to bounce from one SSID to another), turned off Hotspot 2.0 networks, set obtain DNS automatically and tried using Google's DNS (8.8.8.8, 8.8.4.4) and the list goes on. Ran windows network diagnostics. Performed Network reset. Uninstalled, reinstalled, and rolled back drivers. Even ran AVG full/deep scan. Rebooted after each step.

I've unplugged, waited 30 seconds, plugged in both Arris and Netgear. I went to Spectrum web site and did a reset that way.

Here's the kicker; the HP is fine, if I disconnect power from Netgear! I can connect to Work or Work5G and browse away like nothing is ever wrong. With HP, I can ping .250 successfully, every time AND I can ping .1, with HP successfully every time.

As soon as the Netgear is powered up, the HP connects, allows me to browse slowly for about 1 minute, then I get server not found errors, can't reach this page, etc. using Chrome, Edge and Firefox.

All other devices use the Amp or Amp.5G to connect, as they had in the past, so I never had to reconfigure any other devices.

I'm at my wit's end. Any help, suggestions or configs you can suggest, would be much appreciated. The HP has no Ethernet port, so a wired connection isn't possible.

:)

 

laptop will not connect to wifi extender

my room is far from the wifi so I got an internet extender but my laptop wont connect to it ...

but when am near the wifi ( not the extender ) it connects .. what should i do ?

 

my son laptiop wifi disconnect after 5 minutes

• If you have an identical laptop try comparing the wifi and security settings of the one that does not disconnect with the one that does. If you find any differences change the settings of the one that does not work to the one that does.

• If you do not have an identical laptop see this post and the three replies for possible solutions: Wifi disconnects every 5 minutes.

@Samuria : If you have any suggestions please reply.

 

connecting to my wifi extender

I cannot connect to my wifi extender (netgear) from my laptop. I have Windows 10 installed. I can connect with all other devices (cell phones).

I can connect to my modem/router but when trying to connect to the extender it says "internet not available". Any suggestions or has this nothing to do with Microsoft products?