function FindXPath([System.Xml.XmlNode]$node) {
    [string]$cur = ''
    if($node -ne $null){
        if($node.NodeType -eq [System.Xml.XmlNodeType]::Attribute) {
            $cur = "/@[$($node.Name)]"
        } elseif($node.NodeType -eq [System.Xml.XmlNodeType]::Element) {
            $cur = "/$($node.Name)"
        } elseif($node.NodeType -eq [System.Xml.XmlNodeType]::Document) {
            $cur = ""
        } else {
            $cur = "Not Supported"
        }
        $cur = "$(FindXPath($node.ParentNode))$($cur)"
    }
    return $cur
}

[xml]$xml = Get-Content $xmlfile

$nodes = $xml.SelectNodes("//Guid")
$nodes | % { FindXPath $_ }