I had a strange problem unsolved !

I have modified my main kix script that call other small kix scripts. In one of the small script, I call by RUN command IESETUP.EXE.
The exact sintax is
RUN "\\WESTERN\INSTALL$\AUTOINST\IE5\FLAT\WIN32\FR\IE5SETUP.EXE".
It was previously working and not anymore.
Is there any bug known in RUN COMMAND ?

Thanks