Microsoft Script Debuggers opens without an error inside

Hi all,
I've this strange problem.
I've deployed a big and complicated ASP web application on different
web server, all of them installed with Win 2000 Advanced Server SP3.

I'm completly sure that my web application has no asp errors, but
randomly and sometimes on one of these server Microsoft Script Debugger

opens without an error inside.


In that moment there are no error because the IIS is not blocked as
when a asp error is shown inside Microsoft Script Debugger.


Why does it happen ?


best regards