How to prevent Media Folder (Music and TV) return to default after power outage?

If power outages are common in your area, have you considered using a UPS?
Excellent response. Still same thing will happen when I shut down computer for any reason. In systems before Mountain Lion this would not change. Why it is happening again there is no possible explanation. All they have to do is include the file screen to the already available lock in the restrictions. Thanks for response.
Ah, OK. I thought by your first post that you were losing the default setting to your pictures, or music folders.
So, your selected folders are on an external drive?
Can you give other details -- such as, what kind of connection to your external drive? (connected and powered through a hub, or is the drive self-powered (the drive has its own power supply).
You said that everything seemed OK before Mountain Lion... What version of macOS are you using now (and which model Mac?)