2486 Views 7 Replies Latest reply: Dec 27, 2009 11:13 AM by Allan Eckert
Open Disk Utility. Select the main drive heading (Mfgr.'s ID) from the sidebar list. Look to the status area at the bottom of the window. How is the drive partitioned? Does it say GUID? Is the drive formatted Mac OS Extended, Journaled? I'm guessing your drive may be partitioned APM in which case you cannot install OS X until you repartition the drive. That will erase the drive.
I assume you did boot from the Snow Leopard DVD?
OS X cannot be installed anew to a non-GUID partitioned drive. If your drive is partitioned MBR, then you must have done that in the past and cloned an existing system to the drive, because no version of OS X will install on an MBR partitioned drive. You can clone an existing system but not install one from an installer disc.
Backup your Home folder and re-prep the drive:
Extended Hard Drive Preparation
1. Boot from your OS X Installer Disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu.
2. After DU loads select your hard drive (this is the entry with the mfgr.'s ID and size) from the left side list. Note the SMART status of the drive in DU's status area. If it does not say "Verified" then the drive is failing or has failed and will need replacing. SMART info will not be reported on external drives. Otherwise, click on the Partition tab in the DU main window.
3. Under the Volume Scheme heading set the number of partitions from the drop down menu to one. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, set the partition scheme to *GUID (for Intel Macs)* or APM (for PPC Macs) then click on the OK button. Click on the Partition button and wait until the process has completed.
4. Select the volume you just created (this is the sub-entry under the drive entry) from the left side list. Click on the Erase tab in the DU main window.
5. Set the format type to Mac OS Extended (Journaled.) Click on the Options button, check the button for Zero Data and click on OK to return to the Erase window.
6. Click on the Erase button. The format process can take up to several hours depending upon the drive size.
After formatting is completed quit DU and return to the installer. Complete the installation.