I am using C# in Windows 11.
PhotoViewer is the default app for AVI files on my PC. I am trying to launch PhotoViewer with an AVI file using the "Process.Start" method as follows:
MessageBox.Show(fn + " exists? " + File.Exists(fn));
Process.Start("@" + fn);
The MessageBox output is "d:\dscf0001.avi exists? true."
Process.Start throws a Win32Exception with the message "The system cannot find the file specified."
What am I doing wrong?