Modifying PPT files programatically

[Kirti]

Hi,
I have a one ppt file.
I want to some modifications to this file
programatically.
This ppt has 2 slides.
Each slide has one button.
In Action Settings property -> Run command of this
button, there is one exe name. I have to remove this exe
name from run command and enter new exe name.
It's giving error that this object doesn't support
this property.
Below i am giving the code. The code is written in
C#.net.

if(objActionSetting.Action ==
PowerPoint.PpActionType.ppActionRunProgram)

{

string strRunText = objActionSetting.Run;

strRunText = strRunText.ToUpper();


if(strRunText == "VWPPV8L.EXE -S=C")
{

objActionSetting.Run= "CBTFileWriter.exe";

}
}

Please help me out in this problem.
Thaking you.