I would start with the minimal setup. Connect one of the non working machines to just the the switch, just to rule out any other equipment. Test all ports with this PC. repeat with the other two. Where are the similarities? Is something different?
Also, the TL-SG105E is a managed switch. Connect it to the working PC and open the web interface. Default IP of the switch is 192.168.0.1 if there is no DHCP lease. Make sure the IP is not used twice in your setup. Make a fimrware update, make a factory reset on the switch.
