Mac drive disappeared

My Mac is MBA with OS X 10.6.8 (bought 3/30/2011) and Windows 7 is installed on it by using Boot Camp Assistant.

Option/Reboot lists only Windows drive and OS X drive no longer shows up. How can I recover the Mac drive? I have an external USB drive from which OS X 10.6.8 can be booted and can be used for trouble shooting purposes.

Reset the NVRAM and try again. If it refuses to show Snow Leopard as a boot option, post back.

I did resetting NVRAM by following the article at the link, but the Snow Leopad is still not shown as a boot option.

I'm not sure what happened to your system in that Snow Leopard can no longer be booted? When you boot from the external USB drive and access the MBA hard drive, can you see the OS X Snow Leopard partition at all?

I'm thinking it may have been overwritten by Windows 7 when you installed it. It's possible that you could have formatted the Snow Leopard partition along with Windows 7. Anyway, it looks like you probably will have to reinstall Snow Leopard to set things straight.

chscag said:

I'm not sure what happened to your system in that Snow Leopard can no longer be booted? When you boot from the external USB drive and access the MBA hard drive, can you see the OS X Snow Leopard partition at all?

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I booted from the external USB drive but the OS X partition of the internal hard drive(SSD) was not shown. I tried the "Repair Disk" by using the Disk Utility but it said "Disk Utility can't repair this disk"

I'm thinking it may have been overwritten by Windows 7 when you installed it. It's possible that you could have formatted the Snow Leopard partition along with Windows 7. Anyway, it looks like you probably will have to reinstall Snow Leopard to set things straight.

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Is there any third party disk utility to repair the partition. Otherwise, I understand reinstallation of OS X means the remaining two partitions(W7 partition and data partition) have to be erased. Is there a way to save these two partitions as are?

Unfortunately, if the OS X partition was overwritten it means that it will have to be re-created and that will destroy your other partitions. There's no way to recover in that situation. Backup your Windows 7 partition using the Windows 7 built in image backup. You'll need an external drive formatted to NTFS in order to do that though.

Once you get OS X reinstalled, use the Boot Camp assistant to create a partition for Windows 7 and install Windows 7. Once it's installed, you can use your Windows 7 DVD to boot with and recover the image you made. Be sure to read the Microsoft instructions for making the image and recovering it.

And, my advice is to forgo any data partition creation. Creating that data partition might be what wiped out your OS X partition.

It is almost certainly the creation of the data partition that did you in. Boot Camp works ONLY with 2 partitions. It can't run on more. So, if you used it to create your Windows installation, then when you used Disk Utility to create a third partition, something had to give ... and presto. No OSX.

You really DON'T need a data partition even when running in Windows in Boot Camp. The Boot Camp partition will not affect your OSX partition. Sorry you have so much work ahead of you.

+1 for not creating more than 1 extra partition ... if you really need to do that, you'll have to use reFit (there are many threads on it) but it's much more complex.

Cheers

SammySlim said:

It is almost certainly the creation of the data partition that did you in. Boot Camp works ONLY with 2 partitions. It can't run on more. So, if you used it to create your Windows installation, then when you used Disk Utility to create a third partition, something had to give ... and presto. No OSX.

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It was not that the OSX disappeared moment after the data drive was created. Both OSes were working fine until the Boot Camp Software update v.3.2 was installed.

I have not installed the Snow Leopard yet because I misplaced the reinstall USB drive and could not find it until today. I am leaning towards installing the Lion instead.

I have not installed the Snow Leopard yet because I misplaced the reinstall USB drive and could not find it until today. I am leaning towards installing the Lion instead.

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If you intend to install Lion, my advice it to start over with creating a Boot Camp partition and installing Windows. Lion by default will create a hidden recovery partition on the drive.

I downloaded the Lion install file and have just created the Lion install USB drive from it. But I am still wondering if switching to Lion is too early for me since I got the Mac only four months ago for the first time. I purchased a couple of reference books for Mac that cover the Snow Leopard. On the other hand, I would think there is no drastic changes of its UI so that those books are mostly still usable for the Lion.
Comments are appreciated.