RFID RC522 interface with Arduino uno and ethernet shield

Hello everyone,
I sucessfully interfaced RFID RC522 reader and lcd display with Arduino Uno. so whenever i scan my card, display shows 'hi nikhil"
Now i want to communicate this information that my card has been scanned to the computer via arduino ethernet shield and router. computer is on the same router. i placed the ethernet shield on arduino and ran basic programs which executed properly but when i made the lcd and rfid reader connections, the card wasnt being read. i did assign mac and ip address to the shield.what do i do now??