How do I determine the owner of a process in C#?

I am looking for a process by the name of "MyApp.exe" and I want to make sure I get the process that is owned by a particular user.

I use the following code to get a list of the processes:

Process[] processes = Process.GetProcessesByName("MyApp");

This gives me a list of processes, but there does not appear to be a way in the Process class to determine who owns that process? Any thoughts on how I can do this?

You can use WMI to get the user owning a certain process. To use WMI you need to add a reference to the System.Management.dll to your project.

By process id:

public string GetProcessOwner(int processId)
{
    string query = "Select * From Win32_Process Where ProcessID = " + processId;
    ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
    ManagementObjectCollection processList = searcher.Get();

    foreach (ManagementObject obj in processList)
    {
        string[] argList = new string[] { string.Empty, string.Empty };
        int returnVal = Convert.ToInt32(obj.InvokeMethod("GetOwner", argList));
        if (returnVal == 0)
        {
            // return DOMAIN\user
            return argList[1] + "\\" + argList[0];
        }
    }

    return "NO OWNER";
}

By process name (finds the first process only, adjust accordingly):

public string GetProcessOwner(string processName)
{
    string query = "Select * from Win32_Process Where Name = \"" + processName + "\"";
    ManagementObjectSearcher searcher = new ManagementObjectSearcher(query);
    ManagementObjectCollection processList = searcher.Get();

    foreach (ManagementObject obj in processList)
    {
        string[] argList = new string[] { string.Empty, string.Empty };
        int returnVal = Convert.ToInt32(obj.InvokeMethod("GetOwner", argList));
        if (returnVal == 0)
        {
            // return DOMAIN\user
            string owner = argList[1] + "\\" + argList[0];
            return owner;       
        }
    }

    return "NO OWNER";
}

Since WMI is not always a fast way of retrieving information, here is the native P/Invoke way of doing it:

The return value is null when unsuccessful. In order to get the names of processes running under the SYSTEM user, you need to execute this code as administrator.

private static string GetProcessUser(Process process)
{
	IntPtr processHandle = IntPtr.Zero;
	try
	{
		OpenProcessToken(process.Handle, 8, out processHandle);
		WindowsIdentity wi = new WindowsIdentity(processHandle);
		string user = wi.Name;
		return user.Contains(@"\") ? user.Substring(user.IndexOf(@"\") + 1) : user;
	}
	catch
	{
		return null;
	}
	finally
	{
		if (processHandle != IntPtr.Zero)
		{
			CloseHandle(processHandle);
		}
	}
}

[DllImport("advapi32.dll", SetLastError = true)]
private static extern bool OpenProcessToken(IntPtr ProcessHandle, uint DesiredAccess, out IntPtr TokenHandle);
[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CloseHandle(IntPtr hObject);

Here is the VB version for the non C# speakers:

Function GetProcessOwner(ProcessName As String) As String
    Dim query = "Select * from Win32_Process Where Name = """ + ProcessName + """"
    Dim searcher = New ManagementObjectSearcher(query)
    Dim processList = searcher.Get()

    For Each obj As ManagementObject In processList
      Dim argList As String() = {String.Empty, String.Empty}
      Dim returnVal = Convert.ToInt32(obj.InvokeMethod("GetOwner", argList))
      If returnVal = 0 Then
        ' return DOMAIN\user
        Dim owner = argList(1) + "\\" + argList(0)
        Return owner
      End If
    Next

    Return "NO OWNER"
  End Function

  Function GetProcessOwner(processId As Integer) As String
    Dim query = "Select * From Win32_Process Where ProcessID = " & processId
    Dim searcher = New ManagementObjectSearcher(query)
    Dim processList = searcher.Get()

    For Each obj As ManagementObject In processList
      Dim argList As String() = {String.Empty, String.Empty}
      Dim returnVal = Convert.ToInt32(obj.InvokeMethod("GetOwner", argList))
      If returnVal = 0 Then
        ' return DOMAIN\user
        Return argList(1) + "\\" + argList(0)
      End If
    Next

    Return "NO OWNER"
  End Function

Unfortunately there's no native .Net way of getting the process owner.

Have a look at these for a potential solution:

• http://msmvps.com/blogs/siva/archive/2006/10/02/Getting-Windows-Process-Owner-Name.aspx
• http://www.codeproject.com/KB/cs/processownersid.aspx

    var myApp = Process.GetProcessesByName("MyApp").FirstOrDefault();
    if (myApp != null)
    {
        string username = GetUsername(myApp.SessionId);
    }

Implementation of method GetUsername here: https://stackoverflow.com/a/35810391/10412686

Add a reference to your project:

System.Management

Then add the following method to your project:

    public string GetProcessOwner(int processId)
    {
        string MethodResult = null;
        try
        {
            StringBuilder sb = new StringBuilder();

            sb.Append(" SELECT ");
            sb.Append("     * ");
            sb.Append(" FROM ");
            sb.Append("     WIN32_PROCESS");
            sb.Append(" WHERE ");
            sb.Append("     ProcessId = " + processId);
            
            string Query = sb.ToString();
            
            ManagementObjectCollection Processes = new ManagementObjectSearcher(Query).Get();

            foreach (ManagementObject Process in Processes)
            {
                string[] Args = new string[] { "", "" };

                int ReturnCode = Convert.ToInt32(Process.InvokeMethod("GetOwner", Args));

                switch(ReturnCode)
                {
                    case 0:
                        MethodResult = Args[1] + "\\" + Args[0];
                        break;

                    default:
                        MethodResult = "None";
                        break;

                }

            }

        }
        catch //(Exception ex)
        {
            //ex.HandleException();
        }
        return MethodResult;
    }

Then add this method:

    public DataTable GetProcessTable()
    {
        DataTable MethodResult = null;
        try
        {
            List<Process> Processes = Process.GetProcesses().ToList<Process>();

            DataTable dt = new DataTable();
            dt.Columns.Add("Name", typeof(string));
            dt.Columns["Name"].ReadOnly = true;

            dt.Columns.Add("Id", typeof(string));
            dt.Columns["Id"].ReadOnly = true;

            dt.Columns.Add("Owner", typeof(string));
            dt.Columns["Owner"].ReadOnly = true;

            foreach (Process p in Processes)
            {
                DataRow r = dt.NewRow();

                bool Match = false;
                    
                r["Id"] = p.Id.ToString();
                r["Name"] = p.ProcessName;
                r["Owner"] = GetProcessOwner(p.Id);
                        
                dt.Rows.Add(r);

            }

            MethodResult = dt;

        }
        catch //(Exception ex)
        {
            //ex.HandleException();
        }
        return MethodResult;
    }

Calling GetProcessTable() gives you a DataTable of all running processes along with their Id and Name, which is handy because it can be used as a DataGridView's Datasource parameter.

Let me know if you need any more fields adding to the table.

WMI is really the worst possible way how to get this information from Process. But... sometimes you need to get that info from remote process, and in that case you sadly need WMI. So if you have to, or want to use WMI, I suggest to do it like this (it's more than 60% quicker then classic WMI methods above):

Method:

public struct WMIProcessProperties
{
    public string Owner;
    public int ID;
}


public static async Task<Dictionary<Process, WMIProcessProperties>> GetWMIProperties(this IEnumerable<Process> processes)
{
    Dictionary<Process, WMIProcessProperties> result = new Dictionary<Process, WMIProcessProperties>();

    if (processes == null || processes.Count() == 0) { return result; }

    string selectQuery = "SELECT Handle, ProcessID FROM Win32_Process";
    selectQuery += processes.Count() <= 10 ? string.Format(" WHERE ProcessID = {0}", string.Join(" OR ProcessID = ", processes.Select(p => p.Id))) : string.Empty;

    using (CimSession session = await Task.Run(() => CimSession.Create(processes.ElementAt(0).MachineName)))
    {
        List<CimInstance> instances = await Task.Run(() => session.QueryInstances(@"root\cimv2", "WQL", selectQuery).ToList());

        List<Task<WMIProcessProperties>> tasks = new List<Task<WMIProcessProperties>>();

        for (int i = 0; i < instances.Count; i++)
        {
            CimInstance currentInstance = instances[i];

            tasks.Add(Task.Run(() =>
            {
                int id = Convert.ToInt32(currentInstance.CimInstanceProperties["ProcessID"].Value);
                string owner;
                using (CimMethodResult getOwnerResult = session.InvokeMethod(currentInstance, "GetOwner", null))
                {
                     owner = getOwnerResult.OutParameters["User"]?.Value?.ToString();
                }

                currentInstance.Dispose();

                return new WMIProcessProperties { Owner = owner, ID = id };

            }));
        }

        WMIProcessProperties[] wmiProcessProperties = await Task.WhenAll(tasks).ConfigureAwait(false);

        for (int i = 0; i < wmiProcessProperties.Length; i++)
        {
            result.Add(processes.Single(p => p.Id == wmiProcessProperties[i].ID), wmiProcessProperties[i]);
        }
    }

    return result;
}

If you want to see little time comparison, see this answer.

Loop through collection to check for permissions. Most cases current user will not be administrator

List<Process> processes = Process.GetProcessesByName(Text).ToList();
for (int i = processes.Count - 1; i > -1; i--)
{
    try
    {
        if (processes[i].MainModule?.FileName is null)
            processes.RemoveAt(i);
    }
    catch (Exception)
    {
        processes.RemoveAt(i);
    }
}

With the help from detecting-user-name-from-process-id I have written the better - quicker - version of this function:

public static string GetProcessOwnerByID(int processId)
{
  IntPtr processHandle = IntPtr.Zero;
  IntPtr tokenHandle = IntPtr.Zero;
  try
  {
    processHandle = OpenProcess(PROCESS_QUERY_INFORMATION, false, processId);
    if (processHandle == IntPtr.Zero)
      return "NO ACCESS";

    OpenProcessToken(processHandle, TOKEN_QUERY, out tokenHandle);
    using (WindowsIdentity wi = new WindowsIdentity(tokenHandle))
    {
      string user = wi.Name;
      return user.Contains(@"\") ? user.Substring(user.IndexOf(@"\") + 1) : user;
    }
  }
  finally
  {
    if (tokenHandle != IntPtr.Zero) CloseHandle(tokenHandle);
    if (processHandle != IntPtr.Zero) CloseHandle(processHandle);
  }
}

Whole file can be found on GitHub gist

System.Security.Principal.WindowsIdentity.GetCurrent().Name