Okay, so you may have a lot of files that you want to get rid of, but you definitely have some files you want to keep. Best of all, this will work with Lion, Mountain Lion, Mavericks, Yosemite, and El Capitan. With just a few clicks of some buttons and your Mac is gonna be running like it did the day you got it. Thankfully, the geniuses over at Apple have made the process easy for us-no need for a disc no need for a drive-all you need is a decent internet connection. Often, the best option to fix these problems would be to reformat your computer and reinstall your OS, but since most of us don't plan on ever taking this drastic measure, we don't obtain a recovery disc or thumb drive. In other cases, your Mac can be experiencing some major malfunctions: constant crashing, locked controls, slow boot times, missing files, etc. At one point, I realized that there were plenty of files on my Mac that I didn't need any more, but too many to delete individually. As I've said before, slowing down is not an option for me.

Mac os x for macbook a1181