We really need more information than you've posted...
Have you examined your configuration?
Have you examined the logs?
What version of software?
What model of card is in the slot?
Which slot?
How did this break?
An easy place to start is connect a device to a port and start a constant ping, then look at the ifInOctets and ifOutOctets on that port, are they incrementing? If they are then you have a configuration problem with the port.
Good Luck!