Error when shutting down computer

Hello,
I have a problem on my Windows 8. When I shut down my computer there is an error that pops up and this error prevents me from shutting down until I shut it using the button. I do not know why this error is appearing please help.

CUcc Platform: msnmsgr.exe-Application Error
The instruction at 0x1000a548 referenced memory at 0x1000a548. The memory could not be written.
Click on Ok to terminate the program
