Network Wiring

Hi, I know this isn't probably the correct area to post this question but I couldn't see another as it is neither Hardware or software.
I have a number of network points (Cat5e) around my home all linked by a non managed hub.
Most of my access is now via wi-fi but occasionally I connect a device via a Cat5 cable. (TV, old computer etc.)
Recently, when I have connected a device there has been no internet available.
I tested all the cables and all tested fine.
The Hub also appears to be working i.e. the LED for each port illuminates if there is a device on that network point, but no internet.
Any thoughts on how to cheaply test and discover what could be the problem.

I retired from my computer job several years ago so there is no-one there to ask or borrow equipment from, so all I have is the cable tester and a multimeter.
Thanks for any thoughts you may have and have a merry Xmas and New YEar

 

Other than swapping in a different hub (a switch would be better) I don't know of another way.

How did you test the cables? Do you have a tester? Or by swapping?

How many ports? You can spend a lot of money on a switch, but don't have to. There are many 4 or 8 port switches for less than $50.

 

After plugging in to the hub you see the port light up, have you ran an ipconfig to see if you got an IP? Disable then Enable the NIC? Check the NIC properties, see if it is set for DHCP.
Reset the hub.