Hey Doug I have an old Mac I want to give to a friend. But I don't want to give them my personal files. I know I can just delete the files but then it is possible with some software mechanism to retrieve those files later. How can I securely delete the files so no one, no matter how evil can get at them again later?
Gee Ken with friends like that...
Well you can make sure the data has been erased. It is very easy on the Mac.
1. Find all of the data that you want to delete. This will most likely be in your Download and documents folder.
2. Launch Disk Utility - Command button 3 times and type in Disk Utility and click enter.
3. Select the drive that you want to clear deleted data.
4. Click the Erase tab and click on Erase Free Space.
5. The next screen popup with a choice for different security levels of data erase.
6. Depends on your MAC OS you can see selections or a slider to choose these options
Fastest: Zero Out Deleted Files, 7-Pass Erase of Deleted Files, Most Secure: 35-Pass Erase of Deleted Files.
The default option Zero Out Deleted Files, writes zeros over the drive’s free space would be sufficient for the most of the cases. You can go up to more secure option if you want, but it will take a very long time.
I would recommend taking a back up before securely erasing the data on your hard disk for peace of mind.
Now your friend will be able to use your computer and you can feel secure in that your old data will not be seen.