The connection to your computer was lost SOPCAST

My SOPCAST software keep throwing error message that the connection to computer was lost. I am plugged in to my network. I know for sure all my connections are plugged in.
I confirmed that I am able to share my files from my PC. Not sure what this error exactly means. My machine has Windows XP SP3 installed on. My firewall is also turned OFF.
Can anyone suggest any ideas for the below error message?

The connection to your computer was lost.
Make sure your computer is turned on,
connected to your network, and running
media sharing software.
Status code: 53-C00DF238
