rj8CDyAf.exe

I am working with a machine right now (windows xp home) that has been giving me nothing but problems, thus far I have been relatively successful at resolving most but right now i am getting a strange error and i could use a little help if anybody out there has any ideas.
the error is as follows:
“rj8CDyAf.exe – application error
the instruction at “0x7c9118c5” referenced memory at “0x006f0036″ the memory could not be read” please help