alutLoadMemoryFromFile problem

This is part of a function that loads sound for my sprite game made in C# and Tao.

int format;
float frequency;
int size;
IntPtr data = Alut.alutLoadMemoryFromFile(path, out format, out size, out frequency);
System.Diagnostics.Debug.Assert(data != IntPtr.Zero, "alutLoadMemoryFromFile failed.");


On my PC this Assert is fine. I gave my game to few people and on their computers this Assert fails. What could possibly be the reason?

Thank you