I will add to the above that you should not use DHCP and instead write down each machine and assign it a fixed unique IP address. Then manually set each machine to its assigned address. This will permanently eliminate future IP address conflicts.
But your problem may be that you are using the wrong type of cable i.e. crossover vs. regular. Some switches have auto switching ports that deal with wrong cable types and adjust for speed and duplex. If your switch is basic, you may need to set your printer to the correct speed and duplex supported by the switch.
If the above doesn't help, it is possible that you your switch has a firewall that is blocking the port(s) your printer uses. If so, you would need to unblock the port(s) by logging in to the switch from a web browser.