Windows 2019: elastic-agent and endpoint security

Hello,
I'm testing the endpoint-security feature through Elastic Agent. I was able to install and enroll the agent, but I have this error in the logs:

{"log.level":"error","@timestamp":"2020-11-17T12:19:09.127+0100","log.origin":{"file.name":"application/fleet_gateway.go","file.line":159},"message":"failed to dispatch actions, error: operator: failed to execute step sc-run, error: operation 'Exec' failed: : operation 'Exec' failed: ","ecs.version":"1.6.0"}

I'm using 8.0.0 snapshot, for all the components: Elasticsearch, Kibana and Agent. The build number is 8.0.0-b557611c.
The powershell version is 5.1, and the ElasticAgent service is running as Local System account.

Is there any other Windows configuration to perform?

thanks,
Fausto