Force lock windows after set time

Task Scheduler is one option. For what the OP wants, two tasks are needed: one to be executed 30 minutes after log on, another to be executed 30 minutes after each consecutive unlock.

Here's how:

1. In Task Scheduler, select Create Task:
   
   
   
2. Name the task, click Change User or Group:
   
   
   
3. Type the group name Users to Enter the object name to select, click Check Names:
   
   
   
4. Select the group YOUR_COMPUTERNAME\Users, click OK:
   
   
   
5. Switch to Triggers tab, click New:
   
   
   
6. Select Begin the task: At logon
   
   
   
7. Select Any user, select Delay task for and select 30 minutes from the drop down list, click OK:
   
   
   
8. Switch to Actions tab, click New:
   
   
   
9. Select Action: Start a program, type the command rundll32.exe to Program/script field, type the command arguments user32.dll, LockWorkStation to Add arguments, click OK:
   
   
   
10. Click OK to save the task:
    
    
    

This task will lock the computer 30 minutes after any user logs in but thereafter when user unlocks the computer, task will no longer work. For this we need a second task. Repeat the above task creation process, create a similar task except at step 7 change the Begin the task to On workstation unlock:

This second task will take care of locking the computer 30 minutes after each unlock after the initial locking 30 minutes after the log in.

Should work :).

Kari

Kari, another great tutorial. Should be added to the tutorials section.

Ztruker said:

Kari, another great tutorial. Should be added to the tutorials section.

Agreed.

Sorry Kari, I'm not allowed to Rep you.

   Note

Please notice that I have edited my previous post; in my tests the tasks did not run every time for every user.

I have changed the Step 2 to use a group (Users) instead of individual admin user. As this change requires two additional steps, the steps 3 and 4 were added.

The tasks will now run every time for every user.

galili said:

Thanks a lot, Kari & Ryan2320, I'll try this and update if it works as I wanted.

Another question, if I may - how do I add a message to the user 1 minute before lock, to let him know that the system will lock in 1 minute?

OK, then the message. One solution would be to create two additional tasks to display a message every time one of the two tasks we created will be run. However, this would not be very practical. A simpler solution is to use batch files. The below examples will show a message to the user 30 seconds before locking the computer. You can change the time value to whatever you want to.

A simple but not so elegant solution:

• Run Notepad as administrator to be able to save directly to protected system folders
• Create a simple batch file to be saved in the ProgramData folder:
  
  Code:

  @echo off
  echo The computer will be locked in 30 seconds.
  timeout /t 30
  %windir%\System32\rundll32.exe user32.dll, LockWorkStation

• In Notepad, select Save As
• Type %programdata% in Save As dialog's addressbar, hit Enter to access hidden and protected system folder ProgramData:
  
  
  
• Name your batch file, add the .bat extension, select Save as type: All files, click Save:
  
  
  
• Open Task Scheduler and edit both the tasks you created here (in my previous post). Change the Step 9 by changing the Program/Script to %programdata%\LockComputer.bat (or whatever name you gave to batch file), leave the Add arguments field empty, click OK:
  
  
  
• Now when the tasks are run, the user will see a message in Command Prompt and Windows will be locked 30 seconds after the message has been shown:
  
  
  

A bit more elegant solution:

• Run Notepad as administrator to be able to save directly to protected system folders (we will save all three files below to ProgramData folder)
• Create a script file:
  
  Script:

  message = "";
  for (i = 0; i < WScript.Arguments.length; i++) 
  {message = message + WScript.Arguments.Item(i) + " ";}
WScript.Echo(message); 

• In Notepad, select Save As
• Type %programdata% in Save As dialog's addressbar, hit Enter to access hidden and protected system folder ProgramData:
  
  
  
• Name your script file as LockMessage, add the .js (Java Script) extension, select Save as type: All files, click Save:
  
  
  
• Still using Notepad as administrator, create a simple two line batch file as follows and save it as LockComputer.bat:
  
  Code:

  timeout /t 30
  %windir%\System32\rundll32.exe user32.dll, LockWorkStation

• One more batch: Still using Notepad as administrator, create a simple batch file as follows and save it as RunLockComputer.bat (Red italics = the message text shown to users, edit as you wish):
  
  Code:

  start /min wscript %programdata%\LockMessage.js Windows will be locked in 30 seconds. All your open applications will remain open, you can unlock the computer with your password and continue working for another 30 minutes.
  start /min %programdata%\LockComputer.bat ^& exit

• Open Task Scheduler and edit both the tasks you created here (in my previous post). Change the Step 9 by changing the Program/Script to %programdata%\RunLockComputer.bat (or whatever name you gave to batch file), leave the Add arguments field empty, click OK:
  
  
  
• Now when the tasks are run, the user will see a message and Windows will be locked 30 seconds after the message has been shown:
  
  
  

The above script and batch files explained:

• The script to show message (LockMessage.js) will take any text sent to it with wscript command (which we have in RunLockComputer.bat batch file), and display it on a message window. Command syntax for wscript command is:
  
  Code:

  wscript Script_Name Text to be sent to that script

• The first batch file (LockComputer.bat) is the one that executes the Lock Computer command after a 30 second timeout
• The second batch file (RunLockComputer.bat) is the one we call from the Task Scheduler
  
  • First it tells to system to run Command Prompt minimized and execute the wscript command to run the message script (lockMessage.js), passing the given text to it as the message which we want to display
  • Then it tells the system to run our first batch file (LockComputer.bat) to lock the computer, also minimized, so the user does not see any open Command Prompt windows but only the message box
  • The ^& exit at the end of the second command closes the minimized Command Prompt when both commands have been executed

Should run without issues :).

Kari