My DVD ripping software won't rip my entire disc. It leaves out the last part. HELPP!!!!!!!!!?

I use E.M DVD Copy to rip my music video disc, but it left out the last part, cutting off a song midway. No matter the format, and no matter if i empty my hard drive to make space for it, the software still leaves out THAT LAST PART!!!!!!!! Is it the software's problem, or is it something else? I really need help.