How do you stop the Excel proces from running the following code works on some boxes but not others.It seems that it is impossible to terminate the Excel process.

if(ws != null)
{
System.Runtime.InteropServices.Marshal.ReleaseComO bject(ws);
ws = null;
}
if(wb != null)
{
for(int i = 1 ;i < wb.Sheets.Count; i++)
{
((Excel.Worksheet)wb.Sheets[i]).Delete();
}

System.Runtime.InteropServices.Marshal.ReleaseComO bject(wb);
wb = null;
}

if(excelApp != null)
{
excelApp.Quit();
System.Runtime.InteropServices.Marshal.ReleaseComO bject(excelApp);
excelApp = null;
}

System.GC.Collect();

It is not possible for me to use process.kill because the web based application that this used with ddoes not issue admin rights to its users.