How to programatically restart windows explorer process

Question

I'm working on a windows shell extension, and unfortunately, when making changes to the DLL, I must restart windows explorer (since it keeps the DLL in memory).

I found this program from Dino Esposito, but it doesn't work for me.

void SHShellRestart(void)
{
    HWND hwnd;
    hwnd = FindWindow("Progman", NULL );
    PostMessage(hwnd, WM_QUIT, 0, 0 );
    ShellExecute(NULL, NULL, "explorer.exe", NULL, NULL, SW_SHOW );
    return;
}

Does any one have something they can share to do this?

P.S. I realize that I can go to task manager and kill the explorer process, but I just want to do it the lazy way. Besides, this enables automation.

P.P.S I am using .NET for the development, but the shell restart functionality could be in C, C++ or a .NET language. It will simply be a small stand-alone executable.

Answer 1

After FindWindow use GetWindowThreadProcessId, then OpenProcess, then TerminateProcess.

Answer 2

After some more googling, I came up with the following C# solution:

using System.Diagnostics;
...
static public void RestartExplorer()
{
    foreach(Process p in Process.GetProcesses())  {
       if(p.MainModule.ModuleName.contains("explorer") == true)
         p.Kill();
    }
    Process.Start("explorer.exe");
}

Answer 3

This works for me on Vista:

DWORD dwPID;
HANDLE hExp;
HWND hSysTray = ::FindWindow (TEXT("Shell_TrayWnd"), NULL) ;
GetWindowThreadProcessId (hSysTray, &dwPID);
hExp = OpenProcess (PROCESS_TERMINATE, FALSE, dwPID);

if (hExp)
{
   TerminateProcess (hExp, 0);
}
Sleep (2000);
ShellExecute (NULL, NULL, TEXT("explorer.exe"), NULL, NULL, SW_HIDE);

But I can't find any way to suppress the explore window that opens (I tried, hence the SW_HIDE). On Vista, running explorer.exe without parameters seems to be the same as running "explorer.exe /e" on earlier systems. You'll have to try it for yourself on XP, I don't have it here.

Note: Using TerminateProcess does seem extreme, but posting a WM_CLOSE to explorer provokes a windows shutdown dialog.

Answer 4

A fool-proof solution:

foreach (Process p in Process.GetProcesses())
{
    // In case we get Access Denied
    try
    {
        if (p.MainModule.FileName.ToLower().EndsWith(":\\windows\\explorer.exe"))
        {
            p.Kill();
            break;
        }
    }
    catch
    { }
}
Process.Start("explorer.exe");

Answer 5

A C# solution that provides more certainty that the "right" explorer processes get killed.

using System;
using System.Diagnostics;

...............

public static void RestartExplorer()
 {
 const string explorer = "explorer.exe";
 string explorerPath = string.Format("{0}\\{1}", Environment.GetEnvironmentVariable("WINDIR"), explorer);
 foreach (Process process in Process.GetProcesses())
  {
  // In case we get Access Denied
  try
   {
   if (string.Compare(process.MainModule.FileName, explorerPath, StringComparison.OrdinalIgnoreCase) == 0)
    {
    process.Kill();
    }
   }
  catch
   {
   }
  }
 Process.Start(explorer);
 }