Answers based on a google translation...
First question is did you attempt an in-line upgrade from 4.0 to 4.6? Patch 7 is supported for upgrading. https://kc.mcafee.com/corporate/index?page=content&id=KB70981
Check what ports you choose during the setup and then see if any existing programs are using those ports. IIS is usually the culprit as it uses similar ports to the ePO defaults and once it grabs the ports the ePO (Apache) services fail to start.
Once the services have started then your agents will communicate correctly.