A seu pedido, 99823.
HopelessN00b, Gênio da Rede e Senhor de Tudo Que É I.T. aproveitou a oportunidade para postar uma resposta, aproveitando a minha indecisão!
Me: Is the MySQL service running as the same user that encrypted the directory?
You: Hi Ryan - it is not. Mysql server is running as "Network Service" whereas "Administrator" encrypted the directory. Now is it safe to change the mysql service to run under the administrator account?
Me: I would not recommend that, as that would allow any exploits and bugs that affect MySQL to run as Administrator. I would make a separate service account for it. The thing with EFS is that it uses an X509 certificate/key pair to do the encrypting and decrypting, and that certificate is bound to a particular user account.