thermal printer prints cannot connect to server

See more:

C

im having problems with my thermal printer, when its connected to the internet and turned on i get a message printed out saying it cannot connect to server. when i take the internet cable out of the thermal printer and put it into a laptop the internet works. so dont think its a problem with my internet, could be with the router but im not sure what it could be. i have a website which takes orders from the internet and is then printed out in my shop, its a pizza take away and delivery shop.
hope you lot can help me out, it will be appreciated.