Will this work with FritzOS 7.21?

[bersbersbers]

I get an Invalid Action error:

<?xml version="1.0"?>
 <s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/" s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
<s:Body>
<s:Fault>
<faultcode>s:Client</faultcode>
<faultstring>UPnPError</faultstring>
<detail>
<UPnPError xmlns="urn:schemas-upnp-org:control-1-0">
<errorCode>401</errorCode>
<errorDescription>Invalid Action</errorDescription>
</UPnPError>
</detail>
</s:Fault>
</s:Body>

Could this be due to me using FritzOS 7.21, or what else could be wrong?

[bersbersbers]

It does ;) Just enable TR-064 ("access for apps").