Boot Camp Assistant Error

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I know there is probably a thread for this already, but I am new to forums, and do not know how to easily find it. I'm having problems with Boot Camp. It is telling me that I have to back up the disk and use Disk Utility to format it as a single Mac OS Extended (Journaled) Volume. But I know that my Mac is already a Extended Volume. I know I have enough space to partition but it still fails. It is extremely frustrating, and any help would be awesome. I heard that a defragmentation would help but I do not want to spend 40 bucks on something that "might" work.

Thanks
 
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It certainly sounds like it may be fragmented. Try downloading iDefrag. It has a free trial period, though it's limited to such a small drive size that it's pretty much useless. BUT... it will give you a map of your file layout and you can see how fragmented the drive is.
 

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That error means that you do not have enough contiguous space to create a partition of the size you want. Sometimes a defrag works, other times it does not.

Defragging a Mac drive does not necessarily do the same thing as a on Windows drive. Keep in mind, I have had no need to defrag a Mac since my first MBP 3 yrs ago. From what I have seen reported though, a defrag will defrag files, but it does not necessarily relocate your data to the front of the drive like you would expect to see with a good Windows defrag application.

The other way to accomplish this is to backup your machine. You are backing up your system, right? If no, grab SuperDuper! or CarbonCopy Cloner, create a bootable backup to your external drive, boot to the external and then use it to restore back to your internal drive. This is a roundabout way to write everything back to the front end of the volume and provide that needed contiguous space to be able to create a new partition for BootCamp.
 
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An external hard drive is my next purchase for sure. Thanks for the help! That definitely helps out a lot. I greatly appreciate it.

Great Info, Thanks!!
 
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Defragging a Mac drive does not necessarily do the same thing as a on Windows drive. Keep in mind, I have had no need to defrag a Mac since my first MBP 3 yrs ago. From what I have seen reported though, a defrag will defrag files, but it does not necessarily relocate your data to the front of the drive like you would expect to see with a good Windows defrag application.

I hate to outright dispute this, but a defrag on OS X is (or can be) the exact same thing as on a Windows drive. With iDefrag in particular, there are 5 levels of defrag options, with the "full defrag" option moving everything to the front and rearranging files most-frequently accessed to the very front. And while I can appreciate that everyone won't necessarily benefit from a defrag in OS X (OS X does auto-defrag very small files), I have seen very tangible improvements for myself. In one case, it was the only thing that restored my old Powerbook to sane boot times (which was well in excess of 5 minutes). Most recently, it resolved issues I was having streaming videos to my HTPC. Took two full overnight runs to defrag that drive completely.. *whew*

However, the SuperDuper tip is a nice and dirty trick to compact everything contiguously for the purposes of repartitioning.
 

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Like I said I've never done a defrag, so don't really know. Downloaded iDefrag once, on a system that'd been up and running for close to 2 years and it reported my system as less than 0.5% fragmented and dumped it.

I'll certainly take your word that it will work. However, I have seen a whole lot of posts with people reporting doing a defrag with iDefrag and still not getting the contiguous space they needed to create a BootCamp partition while having plenty of free space on their drive. So, I am only making "assumptions" based on those reports.

It is entirely possible they didn't know how to use it, or if it has 5 different levels of defrag, they didn't use the right one. Since I don't use the app, I'm still waiting to see a post in the scenario where someone already tried iDefrag and it didn't provide them with the contiguous space they needed, get help in running iDefrag so that it would.
 
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I'll certainly take your word that it will work. However, I have seen a whole lot of posts with people reporting doing a defrag with iDefrag and still not getting the contiguous space they needed to create a BootCamp partition while having plenty of free space on their drive. So, I am only making "assumptions" based on those reports.

Those people definitely aren't using iDefrag right. To get full access to the disk volume, you either have to boot from a different volume or make a bootable CD with the utility they provide. Barring that, there's very limited value in using it. There is a new major upgrade in beta testing now that gets around these limitations, and to my knowledge iDefrag 2 will be the only defragger for OS X that will be capable of full defrags without booting from a different volume.

I wouldn't bother defragging anything at a mere 1% fragmentation either. But at the 65% I had..... YIKES!
 

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Ahh, thanks for that. Now I comprehend some. I agree, most of them didn't read the BootCamp instructions, doubt they would have learned how to use iDefrag like that either. Plus, I just don't think there are very many of the regulars here using it.

65% - wow - I can only imagine how much slow down you'd have there. Don't think I ever saw anything over 25-30% on any of my windows rigs. If I had seen even 5-10% when I did my testing, I would have bought it.
 
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I tried Idefrag, and I did the "quick" defrag. My boot camp is still failing for the same reason. Would it possibly work if I did the full defrag? How do I make a bootable CD from what they gave me?
 
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I tried Idefrag, and I did the "quick" defrag. My boot camp is still failing for the same reason. Would it possibly work if I did the full defrag? How do I make a bootable CD from what they gave me?

A "Full Defrag" will thoroughly defrag and compact everything. On the Coriolis website, log in and go to "My Account". One of your available downloads should be the Coriolis CDMaker. Use that as directed.

In lieu of the bootable CD, you could make a bootable flash drive if you have one around that is large enough. The advantage to this is you can add/remove tools to the flash drive as needed. And it should be faster.
Bootable Snow Leopard Flash Drive - InsanelyMac Forum
 
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Ahh, thanks for that. Now I comprehend some. I agree, most of them didn't read the BootCamp instructions, doubt they would have learned how to use iDefrag like that either. Plus, I just don't think there are very many of the regulars here using it.

65% - wow - I can only imagine how much slow down you'd have there. Don't think I ever saw anything over 25-30% on any of my windows rigs. If I had seen even 5-10% when I did my testing, I would have bought it.

Yeah.... that 65% shocked me silly. This was a recently installed drive (well a pair of drives... for a RAID mirror) and I had copied everything to it from the old one a week or so earlier. I never would have expected it to be fragmented the way it was.

I first got iDefrag some time back when I was becoming increasingly dissatisfied with some perceived performance slowdowns on my PowerMac G5. Without question, it had a noticeable impact the first time I ran it. I can't recall how fragmented it was, but I'm fairly sure it wasn't more than a couple percents. I doubt my old Powerbook could have been much more than that when it was taking an eternity to boot up... it was never heavily used like the desktops have been.
 

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