If a PowerShell script needs to perform critical steps, and user interaction must be prohibited, you can use API calls to temporarily disable all keyboard input. Locking keyboard input does require Administrator privileges.

Here is a script illustrating how to block all keyboard input for 4 seconds:

#requires -RunAsAdministrator
# when run without administrator privileges, the keyboard will not be blocked!

# get access to API functions that block user input
# blocking of keyboard input requires administrator privileges
$code = @'
    [DllImport("user32.dll")]
    public static extern bool BlockInput(bool fBlockIt);
'@

$userInput = Add-Type -MemberDefinition $code -Name Blocker -Namespace UserInput -PassThru

# block user input
$null = $userInput::BlockInput($true)

Write-Warning "Your input has been disabled for 4 seconds..."
Start-Sleep -Seconds 4

# unblock user input
$null = $userInput::BlockInput($false)

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Anonymous
  • Funny, it never gave me control back. The final line never executed. I had to press the power button on my machine and pretend I was shutting the system down to regain input control. I waited 30 seconds before that...