Fix: Clipboard is not working + Restart-Process with PowerShell

24460391384_1668f05155_m
Sometimes it happens that the clipboard stops working. The routine of copy and paste we all rely on so many times a day suddenly refuses to do its job. The reason this happens is usually an application blocking the keyboard, making it impossible for other applications to get access to the clipboard. In order to fix this, one needs to find out which application is the culprit and either stop or restart the respective process in order to “free up” the clipboard.
I put together a small PowerShell function (Clear-Clipboard), that does just that:

clipboardBlocking

It identifies the process that currently blocks the clipboard (Using GetOpenClipboardWindow and GetWindowThreadProcessId API calls)
Opens a small GUI offering options to either stop or restart the process

Other than the mentioned Clear-Clipboard function. I’m also sharing Restart-Process as a separate function as it might be useful at times. Both can be downloaded from my GitHub repository.

	function Restart-Process{
	[CmdletBinding()]
	param([Parameter(ValueFromPipeline = $true)] $process)
	Begin{
	$selectedIndex=$multiInstanceName=$null
	}
	Process{
	if ($multiInstanceName -eq $_.Name){continue}
	$procToRestart=$_
	#handle if there are multiple instances of the same application
	if ((Get-Process $_.Name).Count -gt 1){
	$multiInstanceName=$_.Name
	$counter = 0
	$processInstances=Get-Process $_.Name
	Write-Host "There are multiple instances of $($_.Name)."
	$prompt+=@("Provide the index of the instance to stop (-1 for all instances first instance will be restarted): ")
	foreach($instance in $processInstances){
	$counter++
	$prompt+="{0} . {1}" -f $counter,$instance.MainWindowTitle
	}
	Add-Type -AssemblyName 'Microsoft.VisualBasic'
	$selectedIndex = [Microsoft.VisualBasic.Interaction]::InputBox(($prompt -join "`n"), "Select Process instance", "1")
	$indices=(0..($processInstances.Length-1))
	switch ($selectedIndex){
	#clicked cancel
	$null {exit}
	#stop all instances but the first
	-1
	{
	$indices=$indices -ne 0
	foreach ($index in $indices){
	$processInstances[$index].Kill()
	$processInstances[$index].WaitForExit()
	}
	$selectedIndex=1
	break
	}
	#mismatching arguments
	{$indices -notcontains ($_-1)}
	{
	Write-Warning "Index is out of bounds.Exit"
	exit
	}
	}
	$procToRestart=$processInstances[$selectedIndex-1]
	}
	$cmdPath,$cmdArguments = (Get-WMIObject Win32_Process -Filter "Handle=$($_.Id)").CommandLine.Split()
	$procToRestart.Kill()
	$procToRestart.WaitForExit()
	if ($cmdArguments) { Start-Process -FilePath $cmdPath -ArgumentList $cmdArguments }
	else { Start-Process -FilePath $cmdPath }
	}
	}

	function GenerateForm($data) {
	Add-Type -AssemblyName System.Windows.Forms
	Add-Type -AssemblyName System.Drawing
	$form= New-Object System.Windows.Forms.Form
	$btnCancel = New-Object System.Windows.Forms.Button
	$btnKill = New-Object System.Windows.Forms.Button
	$btnRestart = New-Object System.Windows.Forms.Button
	$flowPanel = New-Object System.Windows.Forms.FlowLayoutPanel
	$dataGrid = New-Object System.Windows.Forms.DataGridView

	$form.Text = "Process blocking your Clipboard"
	$form.DataBindings.DefaultDataSourceUpdateMode = 0
	$form.AutoSize = $true
	$form.Width = 800

	$flowPanel.Dock = [System.Windows.Forms.DockStyle]::Top
	$flowPanel.FlowDirection = [System.Windows.Forms.FlowDirection]::RightToLeft

	$btnCancel.Text = "Cancel"
	$btnCancel.AutoSize = $true
	$btnCancel.add_Click({$form.Close()})
	$flowPanel.Controls.Add($btnCancel)
	$flowPanel.AutoSize = $true

	$btnKill.TabIndex = 2
	$btnKill.AutoSize = $true
	$btnKill.Dock = [System.Windows.Forms.DockStyle]::Fill
	$btnKill.Text = "Stop Process"
	$btnKill.add_Click({
	$selectedRow = $dataGrid.CurrentRow.Index
	if (($procid=$Script:procInfo[$selectedRow].Id)) {
	Stop-Process -Id $procid
	}
	$form.Close()
	})
	$flowPanel.Controls.Add($btnKill)

	$btnRestart.TabIndex = 1
	$btnRestart.AutoSize = $true
	$btnRestart.Dock = [System.Windows.Forms.DockStyle]::Fill
	$btnRestart.Text = "Restart Process"
	$btnRestart.add_Click({
	$selectedRow = $dataGrid.CurrentRow.Index
	if (($procid=$Script:procInfo[$selectedRow].Id)) {
	$Script:procInfo[$selectedRow] \| Restart-Process
	}
	$form.Close()
	})
	$flowPanel.Controls.Add($btnRestart)

	$dataGrid.ColumnHeadersDefaultCellStyle.BackColor = [System.Drawing.Color]::LightGray
	$dataGrid.EnableHeadersVisualStyles = $false
	$dataGrid.AutoSizeColumnsMode = [System.Windows.Forms.DataGridViewAutoSizeColumnMode]::Fill
	$dataGrid.DataMember = ""
	$dataGrid.TabIndex = 0
	$dataGrid.Dock = [System.Windows.Forms.DockStyle]::Top
	$form.Controls.Add($flowPanel)
	$form.Controls.Add($dataGrid)
	$form.StartPosition = [System.Windows.Forms.FormStartPosition]::CenterScreen
	$form.add_Load({
	$dataGrid.DataSource = $array
	$dataGrid.AutoResizeColumns()
	$dataGrid.Height = 50
	$form.Height = 80
	$form.refresh()
	})
	$form.ShowDialog()\| Out-Null
	}

	function Clear-Clipboard{
	if (("GetClipboardProcess" -as [type]) -eq $null){
	Add-Type @"
	using System;
	using System.Runtime.InteropServices;
	using System.Collections.Generic;
	using System.Text;
	public class GetClipboardProcess{
	[DllImport("user32.dll", SetLastError = true)]
	public static extern IntPtr GetOpenClipboardWindow();

	[DllImport("user32.dll", SetLastError = true)]
	public static extern int GetWindowThreadProcessId(IntPtr hWnd, out int lpdwProcessId);
	}
	"@
	}
	[int]$processID = 0
	$null = [GetClipboardProcess]::GetWindowThreadProcessId([GetClipboardProcess]::GetOpenClipboardWindow(), [ref]$processId)
	if ($processID -ne 0){
	$script:procInfo = @(Get-Process -Id $processID)
	$array = New-Object System.Collections.ArrayList
	$array.AddRange(@($procInfo \| select Id, Name, Path, Description))
	GenerateForm $array
	}
	}