Outlook Showing in Process even after closing - C#

I am writing a code to such that I will get a trigger when ever outlook opens
Process[] processlist = System.Diagnostics.Process.GetProcessesByName("OUTLOOK");

if (processlist.Count() > 0)
{
MessageBox.Show("Outlook Opened");
}



Works great for the first time when I open outlook, but the message box continue to show even after outlook is closed .


I also checked the background process there is no outlook process running.
Help appreciated :) .