Needed to audit a farm to see if a CodePlex solution was being used in SharePoint Designer workflows.  In my case, I needed to see where the iLove SharePoint  solution was being used. The script below is only targeted at one web and is looking for word “ILoveSharePoint” in the XML.

if ((Get-PSSnapin "Microsoft.SharePoint.PowerShell" -ErrorAction SilentlyContinue) -eq $null) 
{
	Add-PSSnapin "Microsoft.SharePoint.PowerShell"
}

[Microsoft.SharePoint.SPSecurity]::RunWithElevatedPrivileges(
	{

		$resultsarray =@()
		#output file name
		$fileName = "C:\ilsp-" + $(Get-Date -Format "yyyyMMddHHmmss") + ".csv"
		#name of the feature we are looking for
		$wFeatureName = "ILoveSharePoint"

		Function GetFiles($folder)
 { 
			foreach($file in $folder.Files)
			{
				if($file.Name.Split('.')[-1] -eq "xoml")
				{
					$web2 = Get-SPWeb $file.Web.Url
					$wFile = $web2.GetFileOrFolderObject($web2.URL +"/"+ $file.URL)

					if ($wFile.Exists -eq "True")
					{
						[xml]$wXml = (New-Object System.Text.UTF8Encoding).GetString($wFile.OpenBinary());
						$nsDetail = $wXml.OuterXml.ToLower()
						
						$wFeatureName = $wFeatureName.ToLower()
							
						if($nsDetail -Like "*$wFeatureName*")
						{
							$outFolder = $folder -replace "Workflows/",""

							$outObject = new-object PSObject
							$outObject | add-member -membertype NoteProperty -name "URL" -Value $web2.Url
							$outObject | add-member -membertype NoteProperty -name "Workflow" -Value $outFolder
							$outObject | add-member -membertype NoteProperty -name "Created By" -Value $wFile.Author
							$outObject | add-member -membertype NoteProperty -name "Created Date" -Value $wFile.TimeCreated
							$outObject | add-member -membertype NoteProperty -name "Modified By" -Value $wFile.ModifiedBy
							$outObject | add-member -membertype NoteProperty -name "Modified Date" -Value $wFile.TimeLastModified

							$global:resultsarray += $outObject
						}
					} 
				} 
			}

			# Use recursion to loop through all subfolders.
			foreach ($subFolder in $folder.SubFolders)
			{
				GetFiles($Subfolder)
			}
		}

		$WebApplications = Get-SPWebApplication

		foreach($webApp in $WebApplications)
		{
			foreach($site in $webApp.Sites)
			{
				if ((Get-SPSite $site.url -ErrorAction SilentlyContinue) -ne $null) 
				{
					foreach($web in $site.AllWebs)
					{
						if ((Get-SPWeb $web.url -ErrorAction SilentlyContinue) -ne $null) 
						{
							$list1 = $web.Lists.TryGetList("Workflows")
							if($list1 -ne $null)
							{
								GetFiles($list1.RootFolder)
							}
						}
					}
				}
			}
		}

		#output file
		$resultsarray | Export-csv $fileName -notypeinformation

	}
)