How to start a process using WMI ("winmgmts:Win32_Process") with hidden window!?

Question

I try to start processes from MsAccess VBA using WMI

Set process = GetObject("winmgmts:Win32_Process")

Result = process.Create(CmdStr, Null, Null, ProcessID)

That works however this opens a window. .... And I do not want a window, I would like the task without or with a hidden window.

In the example given by microsoft (see link below at the bottom of the page)

'https://learn.microsoft.com/en-us/windows/win32/cimwin32prov/create-method-in-class-win32-process'

Set objConfig = objStartup.SpawnInstance_

objConfig.ShowWindow = SW_NORMAL"

is used to determ the window type.

However using that option does lead to a ^security issue schutdown^ a few lines later when starting the process.

So I need a solution to start a process using WMI without window. Note that I can nu use Shell(), since the Shell() function does not return the correct PID (WMI does).

Below some details what is happening using Microsofts Example code.

the microsoft example code does not work. Actual windows security block it / closes MsAccess.

To be more precise

Set objWMIService = GetObject("winmgmts:" _

    & "{impersonationLevel=impersonate}!\" _

    & strComputer & "
oot\cimv2")

Is accepted ... however adding

Set objStartup = objWMIService.Get("Win32_ProcessStartup")

Does lead to "security close" at line

intReturn = objProcess.Create _

    (strCommand, Null, objConfig, intProcessID)

Answer

I think the code below works.

However note:

that I did see that not every start is successful for reasons not always known
not all applications can be started with a hidden window
some applications need time to start and/or stop
some applications can not be started multiple times in parallel

So it is mandatory to check the result code!

It is possible to extend this function with extra options (directory to use etc, as additional (optional) parameter. But that makes thinks more complex and I do not need that at the moment

Be aware that you need to make this function / the MsAccess or Excel version trusted, otherwise the windows macro security protection will show a popup and the application will be killed,

Sub StartProcessWithWMI(ByRef PID As Integer, ByVal CmdStr As String, ByRef Result As Integer, Optional ByVal HideWindow As Boolean = False)

'>> TO RUN THIS CODE the code / this file MUST be trusted by Windows !! <<

'>> Use e.g. File -> Options -> TrustCenter -> add location of this DB as trusted path

'>> If Result <> '0' the process has not been started !! see below 'ResultCode'

'https://learn.microsoft.com/en-us/windows/win32/cimwin32prov/create-method-in-class-win32-process

'PID can be verified via windows taskmanager tab details

'>> ResultCode <<

'Successful completion(0)

'Access denied(2)

'Insufficient privilege(3)

'Unknown failure(8)

'Path Not found(9)

'Invalid Parameter(21)

'Other (22 4294967295)

Dim process As Object



Dim strComputer As String

Dim objWMIService As Object

Dim objStartup As Object

Dim objConfig As Object

strComputer = "."   'local computer name is specified using '.'

Set objWMIService = GetObject("winmgmts:" _

     & "{impersonationLevel=impersonate}!\" _

    & strComputer & "
oot\cimv2")

Set objStartup = objWMIService.Get("Win32_ProcessStartup")



If HideWindow Then

    Set objConfig = objStartup.SpawnInstance_

    objConfig.ShowWindow = vbHide

Else

    Set objConfig = objStartup.SpawnInstance_

    objConfig.ShowWindow = vbNormalFocus

End If

 

Set process = GetObject("winmgmts:Win32_Process")

Result = process.Create(CmdStr, Null, objConfig, PID)

Set process = Nothing

Set objConfig = Nothing

Set objStartup = Nothing

Set objConfig = Nothing

DoEvents

End Sub

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How to start a process using WMI ("winmgmts:Win32_Process") with hidden window!?

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