Unable to debug on Windows xp even if Visual studio 2008 and debugging tools for windows installed

I am unable to debug the hello world application. even though all the required software Visual studio 2008 and latest debugging tools for windows is installed. i identified the problem that QT looks for location %programe files%\debugging tools for windows. but after i installed debugging tools for windows, i also installed the latest WDK (windows driver kit), which copies the windbg to its '"C:\WinDDK\7600.16385.0\Debuggers' directory. i can debug crash dumps with windbg. which means it is correctly installed but since QT looks only for the %programe files%\debugging tools for windows. location. it is unable to locate it. i hope there is a settings for it.