I have tried Yosemite by using it with an external drive but I am want to download it on my computer now. I currently use Mountain Lion OS X 10.8.5. Am I able to go BACK to Mountain Lion if I don't like Yosemite?
MacBook Pro with Retina display, OS X Mountain Lion (10.8.5)
You are using Yosemite from an external drive, correct? Do you not know if you will like Yosemite? Because if you don't yet know, then continue using it until you do.
You can return to Mountain Lion provided:
You are using Yosemite from an external drive, correct? Do you not know if you will like Yosemite? Because if you don't yet know, then continue using it until you do.
You can return to Mountain Lion provided:
Thanks. I read about backing up but NOT in Time Machine. It said to use Disk Utilities and Partition the external drive. I saw an explanation but it wasn't explained enough for me. Is there something that will explain STEP-BY-STEP how to backup NOT USING TIme Machine, As How to Partition, how much to space to partition (how to chose how much space) Etc.
If you have an external drive with sufficient space that you can partition it for separate Mountain Lion and Yosemite partitions, that would be a good solution. Then you can use Time Machine and configure Yosemite to backup to the new partition. The amount of space required for Time Machine is at least twice the capacity of the startup drive.
To resize the drive do the following:
1. Restart the computer and after the chime press and hold down the COMMAND and R keys until the menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD and click on the downward pointing arrow button.
After the main menu appears select Disk Utility and click on the Continue button. Select the hard drive's main entry then click on the Partition tab in the DU main window.
2. You should see the graphical sizing window showing the existing partitions. A portion may appear as a blue rectangle representing the used space on a partition.
3. In the lower right corner of the sizing rectangle for each partition is a resizing gadget. Select it with the mouse and move the bottom of the rectangle upwards until you have reduced the existing partition enough to create the desired new volume's size. The space below the resized partition will appear gray. Click on the Apply button and wait until the process has completed. (Note: You can only make a partition smaller in order to create new free space.)
4. Click on the [+] button below the sizing window to add a new partition in the gray space you freed up. Give the new volume a name, if you wish, then click on the Apply button. Wait until the process has completed.
You should now have a new volume on the drive.
It would be wise to have a backup of your current system as resizing is not necessarily free of risk for data loss. Your drive must have sufficient contiguous free space for this process to work.
Is this so I can have a backup of my Mountain Lion and other programs if I want to go back to Mountain Lion after downloading to the hard drive the Yosemite upgrade? Or is this to test Yosemite prior to downloading to the hard drive or is it both?
It's to create two backup partitions on a single backup drive. That'a what you asked to do. The same procedure will work if you wish to partition your startup drive so you can install Yosemite on it along with Mountain Lion. But if I were you I would install Yosemite on a separate external hard drive.
Always put your backups on drives separate from those with operating systems installed.
How can I go back to Mountainl Lion after upgrading to Yosemite?
