How to solve Still Waiting For Root Device Error

Still waiting for root device error occured because the appropriate Sata/Pata driver isn’t being loaded. This error usually appears before OSX86 DVD can boot and in some cases it occurs after installation. Actually this error means that the OS is set to boot from a drive and partition that does not exist or your bootloader is not able to discover the partition.


Step 1 Jumper Settings : If your system contains IDE hard disk or DVD RW then you need to play with your jumper settings. If the following settings are not working for you try vice versa. if you have Sata Hard Disk and DVD RW skip to step 2.


Your rom/writer must be set as Primary Master.
Your hard-disk must be set as Primary Slave .


Step 2 Tweaking the BIOS : If you satisfies step 1 then time is to play with BIOS settings. Open your BIOS settings by pressing DEL or F2 key continuosly as you starts your PC. Once the BIOS screen appears try to find and change following options if they are available.


ATA/IDE Mode : Native
Configure SATA as : AHCI
S.M.A.R.T. : Enabled




Step 3 The Guide:

If you know the number of your Hard Drive then at the Darwin prompt (after boot press F8) write: rd=DiskX where X is the number of your OSX hard drive.

For instance if your hard drive is 0 (zero is the first hard drive) then write:

rd=disk0

if you do not know your hard drive then there is a try and error method of trying all the disk possibilities on your computer starting with: rd=disk0 then rd=disk1 then rd=disk2 then rd=disk3 etc. another good option is to disconnect other HD and leave the OSX HD as first and write disk0.

How to set the RD for every boot :
once you succeed and don’t want to write the rd parameter every boot, then write it in your boot plist file.this is a file that configure the system boot parameters. The file can be found at:/Library/Preferences/SystemConfiguration

The file name is: com.apple.Boot.plist and you edit it as root and change the Kernel Flags value and add to it the rd parameter like this:

1. Open terminal
2. Write: sudo -s and press enter
3. Enter your password when asked and press enter
4. Write: vi /Library/Preferences/SystemConfiguration/com.apple.Boot.plist and press enter
5. In the vi editor use the arrow keys on the keyboard and navigate the cursor to the tag: after the <key>Kernel Flags< /key > line.
6. The string tag might be empty or not, if it is not empty then add space and then write: rd=diskX where X is your hard drive number.
7. Press keyboard button Esc (in order to exit insert mode)
8. Write: :wq and press enter (notice the : sign)
9. Then reboot and thats it

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