Long Process , not terminating

I have written an application which runs a long process.

On different PCs, this process last around 30mn.

On local PC, with Windows 7 and CF9, no problem, everything is OK.

I have put these lines :

<cfflush interval="10">

<cfsetting requesttimeout = "6000">

Then , I have to put it on the Internet, to let access to different users from external after the long process.

And , on Internet, on a shared serveur Windows 2008, CF9, same conditions,

that long process makes 3/4 of the job, then  the screen never change, nothing happens, no error message.

wait wait, but nothing.

Any help is welcome, to understand this different behaviour from these 2 different environment.

Thanks, Pierre.