Unable to use tradional tools to find memory leaks

[Flamaros]

I tried to used Valgrind (Linux) and Dr Memory (Windows) without 
success to find a big leak I have in my application.
But both tools can't launch my application without make it crash.

Do I need do something particular, to have a chance to see one of 
those tool working fine with my application?

It can be really hard to find leaks manually, maybe some option 
of the gc can help me?