On Sat, 26 Jan 2019 15:06:13 +0000, RobH wrote:

snip

A big oops here as when I tried them connected direct from the router to
a desktop, they all worked.

It now looks like the RJ45 ethernet socket on my laptop has bit the dust.

I would first look inside the socket at the pins and check they
haven't been distorted / miss located.

As I believe has been mentioned, you can easily plug a Type A USB plug
into an RJ45 socket and 'sometimes' the pins get bent, losing their
shape and so tension.

I have generally been able to straighten and re-tension the pins using
a couple of small flat-bladed screwdrivers and some quality fine
tweezers.

And / or one bent, they don't it back in the right places (little
'bays' in the socket moulding).

Or it could also have been damaged electrically / just failed. ;-)

If the Ethernet port is on the mobo then you might find a new Mobo on
eBay pretty cheaply or it may even be on a 'remote' board (even
cheaper). Or you can use a USB Ethernet adaptor, if you just need
USB for connectivity rather than performance etc.

Cheers, T i m