plug 5 pcs into a 4 port router?

i am trying to get 5 pcs in my work office to be networked on a 4 port router. previously i had them all wirelessly conected but the wifi signal was crap. so we are going wired since it is more reliable.

so we got an electrician to fit all of our ethernet boxes on the walls wireing them all together. but what hes done is, he has joined 1 ethernet plug into 2 wires and put both of them into the 1 port on the router. is this why 2 of our pcs wont connect to the internet? or do i have to configure the router to allow both pcs to work in that port?

the router is a bt 2701HGV-C 2-wire router.

 

Networking does not work this way.

You can not join cable to one port. Lets hope that the computer's network card or motherboard did not get damaged.

To have more ports you buy a Network switch and connect it to the Router with CAT5e , then use the switch's ports as additional ports, and connect the computers that are not connected right now to the switch.

Example for a switch, http://www.newegg.com/Product/Product.aspx?Item=N82E16833156270

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