7 Replies Latest reply: Jan 2, 2013 4:37 AM by mende1
Dev_Daniel Level 1 (0 points)

I have a MacBook pro that is currently running Mac OS X v10.6.8 (Snow Leopard). I need to download Xcode and have found the older version of it that is supposed to work on this version from the apple dev website. I get up until the actual "install" button in the installation wizard and it says this:


"The installation failed. An unknown installation error has occurred. The Installer encountered an error that caused the installation to fail. Contact the software manufacturer for assistance."


When I enter the PDF file that came with the download, it tells me that this is Xcode 3.2.6 for Max OS X 10.6 and iOS 4.3. I am unsure as to why it is not installing. There is more than enough HD space.


Do I have to upgrade to 10.7.4 (Lion) before I can use Xcode?


If yes, how exactly do I go about upgading to Lion? Does it cost? How much? Will it wipe my HD?


It is imperative that that last question is correctly answered because it is not just my laptop, it is shared with someone else.


Please help me ASAP as this is a rather urgent matter.


Thanks in advance,




MacBook Pro, Mac OS X (10.6.8)
  • mende1 Level 10 (91,925 points)

    Welcome to the Apple Support Communities


    I recommend you to upgrade to the most recent OS X version, so you will be able to make applications for OS X Mountain Lion and Lion, too.


    The upgrade to OS X Mountain Lion costs $19.99 in the Mac App Store, so the first thing you have to do is to check if all your apps are supported > http://www.roaringapps.com


    Then, open App Store and purchase Mountain Lion. While the Mountain Lion installer is downloading, you can make a Time Machine backup and/or a clone with Carbon Copy Cloner


    When the Mountain Lion installer has downloaded, the installer will appear, so follow the steps to upgrade to Mountain Lion. After upgrading, open App Store and download Xcode 4 for free.


    The hard disk won't be wiped because of upgrading Mac OS X, but as I said, you must make a backup of your files

  • Dev_Daniel Level 1 (0 points)

    Thanks for the super quick reply!


    I don't use the Mac often, so forgive me if I seem daft, but how do I do the backup? Is it a full backup where it stores all data to a seperate storage device or is it a safety point in case something goes wrong so I can just go back to that point?


    If you could breifly explain how the backup or upgrade works that would be terrific.


    Thanks again,

  • mende1 Level 10 (91,925 points)

    You can make the backup with Time Machine or Carbon Copy Cloner. This applications just copies the whole hard disk to an external disk, so you can recover files quickly if some files are lost.


    It's simple to make a backup. If you are going to use Time Machine, the link I gave you will tell you how to make it, and Carbon Copy Cloner will tell you the steps

  • Dev_Daniel Level 1 (0 points)

    OK but what if we don't have an external hard drive or another storage medium.


    The laptop has got 250 GB of data.


    I have a 3TB external hard drive that I use on my Windows PC but when I plugged that into the MacBook Pro, it said it was read only and can't be written.


    What do you suggest?


    I have found a website that is able to backup the MacBook Pro online but am curious as to whether or not it will be able to restore everything (including apps) onto the new OS.


    Will it?




    Message was edited by: Dev_Daniel

  • mende1 Level 10 (91,925 points)

    You can upgrade without any problem, but I recommend to make a backup in case the installation fails

  • Dev_Daniel Level 1 (0 points)

    Sorry, but just to get this 100% clear, am I able to upgrade from Snow Leopard OS X 10.6.8 to Mountain Lion OS X without having to backup and it wont lose anything.


    The only way it will lose something is if the upgrade goes wrong?

  • mende1 Level 10 (91,925 points)

    You can upgrade without any problem, but if the upgrade fails, you will lose everything. If you can't use an external disk, you can make a second partition on the hard disk with Disk Utility to copy here your data, but in most of the cases, the upgrade is done properly and you shouldn't have any problem