Hi,
I don't know if you resolve your issue since january, but I hope so. If not, I recently got the exact same trouble. It's start last month and I was very frustrated. I follow the instructions in the article you mentionned but that didn't help at all.
And in the last past hour, I finally solved it.
I uninstalled my firewall (Zone Alarm Pro) and restart the PC. The Windows firewall ask me to authorize Eucontrol and MC_Client. That's what I did and then no more message at the start of the PC.
I re-installed my Zone Alarm Pro firewall and everything still working just fine.