Microsoft Message Analyser: Start-PefTraceSession "Enable session MMA-ETW-...." failed

Question

I want to use Microsoft Message Analyzer (MMA) to log the network traffic on my device. It works if I use the analyser-application itself, but if I try to use it in my powershell code I get the error: Start-PefTraceSession : Enable session MMA-ETW-Livecapture-72b80a88-dd53-46a0-96e1-7ea5f9824665 failed.

Powershell-code:

$filename = "C:\Temp\blub" + (get-date -UFormat %H-%M-%S)
$s = New-PefTraceSession -SaveOnStop -Path $filename
$s | Add-PefMessageSource -Source Microsoft-Pef-WFP-MessageProvider
$t = New-PefTimeSpanTrigger -TimeSpan (New-TimeSpan -Seconds 5)
$s | Stop-PefTraceSession -Trigger $t
$s | Start-PefTraceSession

Any ideas what's wrong?

Greetings Blue