iMac Home Sharing not working

My late 2009 iMac 8gb ram has stopped sharing wirelessly (over my home network) eg iTunes library, and Printer, I can use the printer wirelessly from my iPad iPhone etc. the iPad and phone also connect to my Samsung TV so I don't think the issue is the network. I know it's an old iMac but this is the only problem I'm having with it. Any help appreciated.

Trev.