Garmin street pilot c310 nav receiver

Question

can you please help us with following problem..my son has accidently wiped the files off the card that fits into theside of above unit and we can not get the unit to bring up the street routs ,all we can see now is the country[ireland] i have phoned several companies here but no one can help us.unfortunatly we have no installation disc or book on this unit and i can not get one here. any help is very much appricated..pat.