How to reset mac mini to factory settings
We have a mac mini that is running Yosemite and would like to reset it to factory settings. My 10yr old uses it and there isn't any important files on it. I have tried restarting it while holding the command and R key down but it hasn't worked. Any other suggestions?? Really could use the help. Thanks
Mac mini, OS X Yosemite version 10.10.1