PC cannot automatically find proxy settings

so you know that connection is definitely work and is not the issue - if so what did you test it on ? and why do you think its working ?
because in your post you said
so if you are using the wireless and not the powerline connections, then often the wireless is accedently switched OFF
BUT
you have clarified that you are NOT using wireless - but using a cable connection from the PC - via the powerline connectors over the electrical system and so wireless is not involved at all

Is that all correct

can you post back an ipconfig /all please


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ipconfig /all

We would like to see the results from an ipconfig /all - post back the results in a reply here.

If you cannot access the internet with this PC, then you will need to paste the results into something like notepad and then copy onto a machine that can access the internet and post the results in a reply here.
Save the file to a USB flash drive or other removable media. Plug it into the working computer with internet access and copy the file and paste here.

If you do not have another PC - do you have a phone connected to the internet - can you photograph the result and post the image in a reply
Note: you will see entries named Tunnel adapter Teredo Tunneling Pseudo-Interface: we dont need to see that information - JUST the information above those entries

For Windows 8

To open a Cmd Prompt or an Administrator Cmd prompt from the Desktop.
http://www.bleepingcomputer.com/tuto...-in-windows-8/
Use Win + X and choose Command Prompt or Command Prompt (Admin) from the list.

For windows version, XP, Vista, W7

Hold the Windows key and press R

Now type CMD

Now press Enter to open a command prompt box (A new dialogue box - black with white font, will appear on screen ):

In the command prompt window that opens, type the following command:

Note that there is a space before the /ALL, but there is NOT a space after the / in the following command.

ipconfig /all > network.txt & network.txt

It will export the results into notepad and then automatically open the notepad and display on your screen.

Now all you need to do is copy and paste those results into a reply here
to do that:
From the notepad menu - choose Edit - Select all
all the text will now be highlighted
Next
From the notepad menu - choose Edit - Copy

Now go back to the forum - goto the reply and then right click in the reply box and paste the results.
The results from the notepad should now appear in the forum reply.
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