Today I bought a DES-1005D switch so I could connect to the internet using my PC and Laptop at the same time. I have a Modem provided by my ISP but it only has 1 port, so no other computers connect, so instead i got myself a switch, I'm trying to see if it works, but it will not connect to the internet, i remove the cable from where its plugged into the modem and put it into the switch, and also a another cable connected to the laptop to the switch.

For some reason it will not connect, anything I'm doing wrong?

return it -- a switch will not do what you desire -- you need a router.

that said, it should allow ONE system to work, but as soon as you connect the second,
both will loose the connection.

look carefully and the markings; ONE should be an UPLINK -- that is the one to the modem.