Question Wired & Wi-Fi connection directly to router not working on 1 laptop (40 other devices connected with no issue) help?

[horrificsquid]

My laptop has suddenly decided not to connect to my BT Smart Hub 2.
I've tried both on the WiFi and wired. Both connections keep changing ip address every few seconds from the 192.168.1.### to a 169.#.#.# address, which I know suggests the DHCP is not working properly, but I can't seem to fix it.

If I connect to the WiFi extender it works perfectly fine, so that rules out a hardware issue.

Laptop is Windows 11 and up to date.

I have tried everything I can think of (in no specific order):
*reboot router (many times).
*reboot laptop (many times).
*ipconfig flushdns release renew.
*uninstall and reinstall network adaptors.
*reset network settings to factory default.
*forget network.
*forget device on router.

I don't understand how it can be fine on the extender when that is just going through the router anyway. I also don't understand how it's still not working when wired.

There are about 40 devices connected to the router working perfectly fine, this includes other laptops.

It was working perfectly fine, then all of a sudden it disconnected, nothing changed, I was literally just looking on imdb.

Any suggestions?

 

[bill001g]

Not likely dhcp, normally once you get a IP it will keep it until the timer runs out. The interface can actually go down for a couple seconds and it will keep the IP.

It is pretty simple though to "fix?" a dhcp issue just go into the IPv4 setting and set a fixed value. You need to pick a IP outside the scope of your DHCP server on the router. You can likely use 192.168.1.250. The dhcp function on consumer routers tend to start at the bottom of the range and will not get to 250 in most houses.

Maybe the event viewer will give you a clue what is going down.

If it was just wifi then I would blame it on having a poor signal to the main router. It makes no sense though why a ethernet cable to the main router would fail the same as wifi signal to the main router.