UNC Path Bug

$dir = "\\localhost\C$\test\"
$exeName = "X.exe"


echo $dir
echo $exeName

for($i=0;$i -le 5; $i++)
{
    $exe = $dir + $exeName
    echo $exe
    $pinfo = New-Object System.Diagnostics.ProcessStartInfo
    $pinfo.WorkingDirectory = $dir
    $pinfo.FileName = $exe
    $pinfo.UseShellExecute = $false
    $p = New-Object System.Diagnostics.Process
    $p.StartInfo = $pinfo
    $p.Start() | Out-Null
    #$p.WaitForExit()
    #$stdout = $p.StandardOutput.ReadToEnd()
    $exeName = "X_" + $i + ".exe"
    rename-item -path $exe -newname $exeName
}