What OS are you using? I'm guessing it will be Microsoft of some sort. Have you changed any hardware/software recently that could have changed some setting for your shared printer? What can you recall changing or adding or removing or any other thing that might have brought about a conflict before this probelm started? Have you been through the printer troubleshooter? Try googling the error message or Microsoft support.
Finally does the printer still work? Does it work if you disconnect other computer/s it shares with. Check in printer sharing settings..........HTH........m