Terminate workflows automatically

Here is a script to terminate all workflows on task items with a due date of more than 7 days in the future.

#Get Site COllection
$siteCollection = Get-SPSite "http://sharepoint.dev.com/sites/site/"

#Your Shaeproint Site URL
$spWeb = Get-SPWeb "http://sharepoint.dev.com/sites/site/sub-site";
$spWeb.AllowUnsafeUpdates = $true;
$WFManager=$Web.site.WorkFlowManager

$deadline = (get-date).AddDays(7)

foreach($subSite in $spWeb.Webs)
{
$subSite.Title
$subSite.AllowUnsafeUpdates = $true
$WFManager=$subSite.site.WorkFlowManager
$list = $subSite.Lists["Requirements"]

foreach ($listItem in $list.Items)
{
$duedate = [datetime]$listItem["Due Date"]
if ($duedate -gt $deadline)
{
foreach ($workflow in $listItem.Workflows)
{
# Write-Host "internal State: " $workflow.InternalState
if ($workflow.InternalState -ne "Completed")
{
# Cancel Workflow
[Microsoft.SharePoint.Workflow.SPWorkflowManager]::CancelWorkflow($workflow);

# start workflow
$WFAssociation = $list.WorkFlowAssociations | where {$_.Name -Like "*Requirement Reminders"}
Write-Host "wf association $WFAssociation"
$WFManager.StartWorkFlow($item,$WFAssociation,$WFAssociation.AssociationData)
}
}

}

}

$subSite.Dispose()
}

$spWeb.Dispose()