It requires a slight rethinking of your workflow to make use of a new feature (AutoSave) effectively. It's not really any more complicated than how it used to work it's just different. So, if you open something like a template for a letter and make changes, the system will save the changes to the original file. With AutoSave, that's no longer the case, because the system is automatically saving the changes you make regardless of whether you tell it to or not. Once you were done modifying the document, you could just click Save As, rename the file and the original would not be touched. In the old days, you could open a file, make changes to it, and as long as you didn't click Save, the changes wouldn't stick.

This has tripped me up a few times already because it's backwards from how it used to work. Then you can rename your file and keep the original as is. Before you make any changes to the document, duplicate it and then save.

So to keep all your files you’ll need to either (1) upgrade to Snow Leopard first or (2) do a time machine backup before you erase everything, then ‘restore’ from the time machine backup when you install Lion.Here's what I suggest you do. NOTE: IF you want to keep all your files and settings this won’t work. Now Quit out of ‘Disk Utility’ and you will be able to install Lion on your freshly erased Mac. THIS WILL DELETE ALL YOUR FILES OFF YOUR COMPUTER AND YOU WILL LOSE THEM.Ĥ. Don’t install Lion, instead go to ‘Disk Utility’ and then ‘Erase’ your main Hard Drive.

To do this restart and hold down option key until you get a choice to boot from your Hard Drive or the USB Lion. To get a Lion installer you can purchase one on a USB thumbdrive from Apple Store ready to go, or you can purchase and download Lion online from Apple and then make a USB installer – see this post for how.Ģ. I had to delete the old version of OSX, then install Lion from the USB thumbdrive. Here’s how to do a fresh install of Lion.ġ. After installing Lion on my iMac, I wanted to delete everything on my laptop and do a fresh install of Lion. But the installer will not install over an older version of OSX. If you have a Lion installer on a USB thumbdrive, you can use it to upgrade your Mac from Snow Leopard to Lion, but if you have an older version of OS X you can’t upgrade. You need to first upgrade to Snow Leopard OR you can erase everything and do a completely fresh install of Lion.

Apple snow leopard vs lion