Active Directory: Send Messages to all currently logged on Users (msg.exe)

By Patrick Gruenauer on 7. October 2017 • ( 45 Comments )

Do you remember the net send command? And do you remember the security concerns? Last week I played with msg.exe. Msg is the “new” net send. I tried to send a message to all users and computers in my domain. Why? I wanted to instruct all users to close all open programs. And now I want to keep and share this knowledge in form of this blog post.

Introduction (msg.exe)

Msg sends a message to a user. This user must be logged in as a domain user (Domain Profile). Which means that the following only works in a domain environment. For network technicans: msg uses Port 445 (SMB/CIFS). If you send a message to a user you have to provide a computername and a username. Or you can try sending a message to yourself:


msg * "Hallo, this is a test!"

* means, that the message is send to all logged on users. Keep in mind that Windows is a multi-user operating system. Don’t forget the others! 😉

Prerequisites

The headline is somewhat misleading. Yes, we are going to send messages to all users, but actually to all computers. Suppose all your client computers are stored in specific Organizational Unit called Workstations. You want to inform all users logged on to this computers. I am going to use Invoke-Command. Make sure, your client computers accepts Remote PowerShell commands. You can run Enable-PSRemoting on each of them. Or you could configure WinRM by using Group Policies:

Group Policies: Enabling WinRM for Windows Client Operating Systems (Windows 10, Windows 8, Windows 7)

Summary

All Computers must reside in the same domain
WinRM has to be enabled on the client computers by running Enable-PSRemoting or by configuring via Group Policies, as described in the link above. Note that on Windows Server 2012/2016 operating systems WinRM is enabled by default, but not on Windows Client systems.

Sending Messages to all Users: PowerShell and Msg.exe in Action

The following One-Liner gets all the computernames of the OU Workstations in the domain sid-500.com. Afterwards msg is executed for each computer in the OU Workstations. The message is send to all users which are currently logged on.


(Get-ADComputer -SearchBase "OU=Workstations,DC=sid-500,DC=com" -Filter *).Name | Foreach-Object {Invoke-Command -ComputerName $_ {msg * "Please close all open files. The Server will be shut down in 5 Minutes"}}

Client01 is a member of the OU Workstation. Client01 receives the message.

Have fun playing with msg!

Published by Patrick Gruenauer

Microsoft MVP on PowerShell [2018-2024], IT-Trainer, IT-Consultant, MCSE: Cloud Platform and Infrastructure, Cisco Certified Academy Instructor. View all posts by Patrick Gruenauer

45 replies »

John says:

21. October 2022 at 15:29

I got our message to work over our domain but (and this may seem like a simple thing) but how do we get a sound to play when the message hits our computers. I have a sound associated with Instant Message Notification but nothing plays.

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hubertsvk says:

23. August 2022 at 12:51

Hi,
it is not working. I am domain admin and local admin and starting cmd/ps with admin rights but still i got error
PS C:\Windows\system32> msg * “Hallo, this is a test!”
Error sending message to session Console : Error 2147500058
Error [2147500058]:The server process could not be started because the configured identity is incorrect. Check the username and password.

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justanadmin says:

30. April 2021 at 10:19

I’m trying to use a variable for msg but it’s erroring out – see below:

#write-host $x
(Get-ADComputer -SearchBase “OU=Test_Devices,OU=Test_OU,OU=Dept OU,DC=crmc,DC=health” -Filter *).Name | Foreach-Object {Invoke-Command -ComputerName $_ {msg * $x}}

Error message:

Message from STDIN is empty; no message sent
+ CategoryInfo : NotSpecified: (Message from ST…no message sent:String) [], RemoteException
+ FullyQualifiedErrorId : NativeCommandError
+ PSComputerName : DESKTOP-U1NMD2N

Any suggestions?

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- Patrick Gruenauer says:
  
  30. April 2021 at 10:21
  
  Hi, use Read-Host instead of Write-Host.
  
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Michael Perry says:

3. February 2021 at 18:22

I know this is an old thread, but just in case anyone still monitors it, there is a way to speed up the execution of this script.

First, add an IF loop to test if the computer responds to a ping.

Second, use the new multithread option -Parallel available in Powershell 7.

To do this, you need to Install Powershell 7. Just follow:

https://docs.microsoft.com/en-us/powershell/scripting/install/installing-powershell-core-on-windows?view=powershell-7.1#installing-the-msi-package

I use it as follows and run it from the server I am restarting:

(Get-ADComputer -SearchBase “OU=Workstations,DC=blah,DC=blah” -Filter *).Name |
ForEach-Object -Parallel {
IF (Test-Connection $_ -Quiet) {
Invoke-Command -ComputerName $_ {msg * “The server will restart in 5 minutes. Please save and close all open files to prevent data loss.”}
}
}
Start-Sleep -Seconds 300 ; Restart-Computer -Force

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- Patrick Gruenauer says:
  
  3. February 2021 at 18:24
  
  Thank you! A nice demonstration of the Parallel feature in PowerShell 7. great one !
  
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  - Michael Perry says:
    
    5. February 2021 at 17:30
    
    I’m trying to use this same method to run an executable which is located on a shared network location.
    
    I need it to run on each workstation.
    
    Below is what I have, but I am getting
    
    Start-Process: Acces is denied
    
    (Get-ADComputer -SearchBase “OU=Workstations,DC=dynamic-structures,DC=us” -Filter *).Name |
    ForEach-Object -Parallel {
    IF (Test-Connection $_ -Quiet) {
    Invoke-Command -Computername $_ -ScriptBlock {Start-Process ‘<network path to exe' -WorkingDirectory 'c:\windows\temp\' -ArgumentList '/s' -Wait}
    }
    }
    
    Any help would be greatly appreciated.
    
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  - Patrick Gruenauer says:
    
    5. February 2021 at 18:14
    
    It’s difficult to help you in this case, because the code looks good but the error message is clear. You have insufficient rights. Check your account. Domain Admin? Best, P
    
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- justanadmin says:
  
  30. April 2021 at 10:30
  
  Sorry – I was just using that for debugging did not mean to cut and paste it in. I’m trying to create a GUI for this for mass messaging all computers in the organization. $x is created by user input by typing into a dialog box
  
  This is full script that:
  
  #load GUI
  Add-Type -AssemblyName System.Windows.Forms
  Add-Type -AssemblyName System.Drawing
  
  #form
  $form = New-Object System.Windows.Forms.Form
  $form.Text = ‘Data Entry Form’
  $form.Size = New-Object System.Drawing.Size(300,200)
  $form.StartPosition = ‘CenterScreen’
  
  $okButton = New-Object System.Windows.Forms.Button
  $okButton.Location = New-Object System.Drawing.Point(75,120)
  $okButton.Size = New-Object System.Drawing.Size(75,23)
  $okButton.Text = ‘OK’
  $okButton.DialogResult = [System.Windows.Forms.DialogResult]::OK
  $form.AcceptButton = $okButton
  $form.Controls.Add($okButton)
  
  $cancelButton = New-Object System.Windows.Forms.Button
  $cancelButton.Location = New-Object System.Drawing.Point(150,120)
  $cancelButton.Size = New-Object System.Drawing.Size(75,23)
  $cancelButton.Text = ‘Cancel’
  $cancelButton.DialogResult = [System.Windows.Forms.DialogResult]::Cancel
  $form.CancelButton = $cancelButton
  $form.Controls.Add($cancelButton)
  
  $label = New-Object System.Windows.Forms.Label
  $label.Location = New-Object System.Drawing.Point(10,20)
  $label.Size = New-Object System.Drawing.Size(280,20)
  $label.Text = ‘Please enter the information in the space below:’
  $form.Controls.Add($label)
  
  $textBox = New-Object System.Windows.Forms.TextBox
  $textBox.Location = New-Object System.Drawing.Point(10,40)
  $textBox.Size = New-Object System.Drawing.Size(260,20)
  $form.Controls.Add($textBox)
  
  $form.Topmost = $true
  
  $form.Add_Shown({$textBox.Select()})
  $result = $form.ShowDialog()
  
  if (($result -eq [System.Windows.Forms.DialogResult]::OK))
  {
  $x = $textBox.Text
  }
  
  (Get-ADComputer -SearchBase “OU=Test_Devices,OU=Test_OU,OU=Dept OU,DC=domain,DC=com” -Filter *).Name | Foreach-Object {Invoke-Command -ComputerName $_ {msg * $x}}
  
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  - Patrick Gruenauer says:
    
    30. April 2021 at 10:34
    
    You could try putting the Get-ADcomputer command inside the brackets of the If condition. There is something wrong with your $x variable.
    
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  - justanadmin says:
    
    30. April 2021 at 12:26
    
    (Get-ADComputer -SearchBase “OU=TestOU,DC=test,DC=com” -Filter *).Name | Foreach-Object {Invoke-Command -ComputerName $_ {msg * $using:x}}
    
    I had to add $usingx instead of $x to get the variable to work.
    
    Per
    
    “PowerShell script blocks are not lexical closures by default. The scriptblock passed to Invoke-Command does not save the current value of the $Message parameter when being run on the other computer.
    
    When the block is run in the remote session, it is using the current value of $Message in that session. Because that variable is most likely $null, the message is omitted from your command.”
    
    Thanks Patrick for your help and your wonderful script.
    
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  - Patrick Gruenauer says:
    
    30. April 2021 at 17:17
    
    You’re welcome.
    
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fcabrita88 says:

22. July 2020 at 13:40

Hello,

I have tried from a PS with admin rights in one machine from domain, but I receive the following message:

Get-ADComputer : The term ‘Get-ADComputer’ is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

Read several cases about this but still I didnt figure out, how to solve it. Do you know how can be resolved?

Thanks in advance!

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- Patrick Gruenauer says:
  
  22. July 2020 at 13:42
  
  In order to use this commands the AD module must be installed.
  
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jate3 says:

16. December 2019 at 14:53

i have tested it in my test environment and it is working very well, the issue is on my production environment which has a lot of computer accounts, how to i make the script run faster because it takes a very long time for the script to get executed.

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- Patrick Gruenauer says:
  
  16. December 2019 at 14:58
  
  Thank you for your feedback. The script is designed mainly for small and middle environments.
  
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  - jate3 says:
    
    16. December 2019 at 15:10
    
    Thank you very much for your Reply, and i v learnt so much here, my other Question is, what about if am running on maybe 2000 Computer accounts, is there an alternative to this Script? putting into consideration the Prerequisites ?
    
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  - Patrick Gruenauer says:
    
    16. December 2019 at 15:12
    
    I guess SCCM can do this. Just research there are tools that uses a client software installed on your cluents
    
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  - jate3 says:
    
    16. December 2019 at 15:22
    
    Thanks so much, let me research on that. God Bless you
    
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jate3 says:

16. December 2019 at 14:50

The Script Worked perfectly in my Test Environment, but in the Production Environment it takes too Long to get executed. is there anything to help to quicken it?

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Tom - Poland says:

8. June 2019 at 19:15

Hello
If the computer is turned on we receive error messages
[PC1] Connecting to remote server PC1 failed with the following error message: WinRM service can not
finish the operation. Check whether the computer name provided is correct and whether the computer is available on the network and whether the exception is
firewall for the WinRM service is enabled and allows access from this computer. By default, the firewall exception for the WinRM service in
If there are public profiles, restricts access to remote computers that are on the same local subnet. For more
information, see the about_Remote_Troubleshooting Help topic.
+ CategoryInfo: OpenError: (PC1: String) [], PSRemotingTransportException
+ FullyQualifiedErrorId: WinRMOperationTimeout, PSSessionStateBroken
How to send on computers only on-line?

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- Patrick Gruenauer says:
  
  8. June 2019 at 20:22
  
  Hi,
  
  Have you followed the instructions of the prerequisites? WinRM is enabled by default on Windows Client operating systems.
  
  Best,
  P
  
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  - Tom - Poland says:
    
    8. June 2019 at 21:59
    
    Yes everything is set correctly. If the PC is an online message appears. If the PC is offline it receives an error in the script as I wrote. It is very slow to run as there is 100 PC in the network
    
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Fuad Bazarah says:

27. February 2019 at 13:24

put the computer inside the OU. This should solve the problem.

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Jane says:

23. February 2019 at 18:19

not working.
I run this command in power shell:

(Get-ADComputer -SearchBase “OU=HR,DC=mydomaint,DC=com” -Filter *).Name | Foreach-Object {Invoke-Command -ComputerName $_ {msg * “This is Test Message”}}

got this error

Invoke-Command : Cannot validate argument on parameter ‘ScriptBlock’. The argument is null. Provide a valid value for the argument, and then try running the command again.
At line:1 char:118
+ … er *).Name | Foreach-Object {Invoke-Command –ComputerName $_ {msg * …
+ ~~
+ CategoryInfo : InvalidData: (:) [Invoke-Command], ParameterBindingValidationException
+ FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.PowerShell.Commands.InvokeCommandCommand

please help!

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- Patrick Gruenauer says:
  
  23. February 2019 at 20:15
  
  Hi, double check the command on the left side of the pipe
  
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  - Jane says:
    
    24. February 2019 at 7:00
    
    Hi, Now i got this error
    
    Invoke-Command : Cannot validate argument on parameter ‘ComputerName’. The argument is null or empty. Provide an
    argument that is not null or empty, and then try the command again.
    At line:1 char:117
    + … ter *).Name | Foreach-Object {Invoke-Command -ComputerName $_ {msg * …
    + ~~
    + CategoryInfo : InvalidData: (:) [Invoke-Command], ParameterBindingValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,Microsoft.PowerShell.Commands.InvokeCommandCommand
    
    Any idea?
    
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