This is a know error i believe. We had this before SP2. Task in console tells succesfull even the install logs tell you succesfull but the task history wil tell the true story Failed.
After companent patch 417 this was fix,; don't forget to update the agents.
Components patch 2014-265 wil fix lots more issue btw..
I knew the machine had this problem when i deployed a policy; the logs told me "task already deployed bty another policy".... but it didn't. Support can guide you to the fix