There are many options to kill workflows in SharePoint which are built on SharePoint 2010 platform. It is a bit more difficult to terminate those on 2013 platform. Here is a script that terminates all workflows based on their status. It is also possible to filter for specific items with a CAML query and it iterates trough large lists in batch si…

TerminateSpWorkflows.ps1

Add-PSSnapin "Microsoft.SharePoint.PowerShell" -ErrorAction SilentlyContinue

$webURL = "https://webapplication/sitecollection/site"		#change this to the url of the site
$listName = "Listname" 					#change this to the corresponding list

$web = Get-SPWeb $webURL
$count = 0
$countTarget = 0

$spQuery = New-Object Microsoft.SharePoint.SPQuery
$spQuery.ViewAttributes = "Scope='Recursive'";
$spQuery.RowLimit = 2000					#terminates the workflows in batches
$caml = "<Where><Eq><FieldRef Name='Fieldname' /><Value Type='Text'>Contenttofilter</Value></Neq></Where>"   #this filter will be used to terminate workflows on specific items
$spQuery.Query = $caml 


if($web -ne $null) {
    $web.AllowUnsafeUpdates = $true;
    $list = $web.Lists[$listName]
    $wfm = New-object Microsoft.SharePoint.WorkflowServices.WorkflowServicesManager($web)
    $sub = $wfm.GetWorkflowSubscriptionService()
    $wfs = $sub.EnumerateSubscriptionsByList($list.ID)
    $wfis = $wfm.GetWorkflowInstanceService()

    do {
        $listItems = $list.GetItems($spQuery)
        $spQuery.ListItemCollectionPosition = $listItems.ListItemCollectionPosition
        foreach($item in $listItems)
        {
        $countTarget++;
        #Write-Host "Working on item $($item.ID)" -ForegroundColor Cyan

        #SP2013 WORKFLOWS
        $workflowInstances = $wfis.EnumerateInstancesForListItem($list.ID,$item.ID)

        foreach($wf in $workflowInstances) 
        {
            if($wf.Status -eq "Suspended") {			#status to get and terminate, can also be -ne "Completed" or -eq "Started"
                $wfName = $wfs | ?{$_.Id -eq $wf.WorkflowSubscriptionId} | select -ExpandProperty Name
                $wfID= $wf.ID
                $wfStatus = $wf.Status
                $wfListItem = $item.Name
                $count++;

                $wfis.TerminateWorkflow($wf);

                Write-Host "Workflow $($wfName) cancelled for: $wfListItem - $($wf.Status)";
                #write-host "Workflow Title: $wfName Status: $wfStatus ListItem: $wfListItem"
            }
        }

        #SP2010 WORKFLOWS
        <#
        foreach ($workflow in $item.Workflows) 
	    {
            $wfName = $workflow.ParentAssociation.Name
            $wfStatus = $workflow.InternalState

                    
            write-host "Workflow Title: $wfName Status: $wfStatus"

            #Disregard Completed Workflows 
            if($workflow.InternalState -ne "Completed")
            {
                #Cancel Workflows        
			    #[Microsoft.SharePoint.Workflow.SPWorkflowManager]::CancelWorkflow($workflow);
			    Write-Host "Workflow $($workflow.Title) cancelled for: " $item.ID;
                #$count++;
            }
	    }
        #>
        }
    }
    while ($spQuery.ListItemCollectionPosition -ne $null)

    $web.AllowUnsafeUpdates = $false; 
    $web.Dispose();

     Write-Host "Processed $countTarget items and found $count workflows"
} else {
    Write-Host "Web not configured" -ForegroundColor Red
}