Web Forms :: Kill Process For Particular User's Session?

i am using icrosoft.Office.Interop.Excel to read the excel file datas. i need to kill the "EXCEL" process if any runtime error occur or any other "EXCEL" process running before read the excel data. I am using this code to kill the process.

private void KillProcess(string processName)
{
system.Diagnostics.Process myproc = new System.Diagnostics.Process();
//Get all instances of proc that are open, attempt to close them.
try
{
foreach (System.Diagnostics.Process thisproc in System.Diagnostics.Process.GetProcessesByName(processName))
{
if (!thisproc.CloseMainWindow())
{
//If closing is not successful or no desktop window handle, then force termination.
thisproc.Kill();
}
} // next proc
}
catch (Exception Exc)
{
throw Exc;
}
}

Now, My question is if the multiple users running the web application with different sessions then it cause problem right. because this method close all the "Excel" process that are currently running. how to kill the excel process for the particular session.