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I have an early 2008 MacBook with Mac OS X Lion installed. I made a partition with Windows 7 Ultimate which I can boot into by holding the Option key on the Mac keyboard.

Boot Issues

After installing updates on the Windows partition I can't boot the Mac anymore. It won't boot with the Option key held down, it only shows the mouse pointer and nothing else on the screen. Normal boot freezes on gray screen, safe boot doesn't work. I have tried all of those.

Additional Information

I don't have another Mac to do the FireWire boot. I also don't have an OS X installation disk, so I can't boot from disc. What causes these problems? I do have a Mac OS X Lion installation USB drive but I don't want to setup OS X again and/or loose my data.

This is the second time this has happened with this Mac. The first time I didn't even have a Windows partition on the machine, and I suspect that the first time these issues were caused by Firefox updates. Any advice?

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up vote 4 down vote accepted

There are two things that you can try:

  1. Power on the notebook holding Option+Command+P+R to reset the PRAM. This will force the EFI to search for a Mac OS X partition to boot.

  2. Power on holding Command+R to boot into the Lion Recovery system. From there you will be able to run the Disk Utility and hopefully repair the damage that Windows did. Worst case it will allow you to reinstall Lion.

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The reason why your mac stop booting is some how you damaged the mac boot log when you installed the boot camp. Most people format the wrong partion or rename it that tends to mess it up. Your suppose to choose the boot camp partion and the format from there. Then both your mac and windows won't affect eachother

that should explain more for that process. If you're concern about your mac you can boot in your mac os and do archive and install so you won't lose your files and installed application however your windows might need to be reinstalled again.

Good luck

Hope that helps.

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