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I don't have Mac OS X installed on my MacBook Pro, but I have Ubuntu and Windows.

I was following this website's instructions to boot faster into Ubuntu without a 30 second delay. However I can't even burn a rEfit CDR image. Do you know how to burn it?

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up vote 10 down vote accepted

Installing rEFIt - at the sourceforge rEFIt page has a link to the CD Burning Instructions.
You may also want to read this TripleBoot via BootCamp page at the onmac Wiki.

Update on your comments.

  • Extensions .dmg and .cdr are used for Disk Images created on Mac
  • I suspect the Windows/Linux target file 'rEFIt-0.14.cdr.gz' is a gzipped ISO
    Try the following,
    • gunzip the 'rEFIt-0.14.cdr.gz' to 'rEFIt-0.14.cdr' and,
    • Rename 'rEFIt-0.14.cdr' to 'rEFIt-0.14.iso'

If you don't have 'gunzip' handy, use 7-zip.


  • The file is just under 7MB so I downloaded it and tried some of the steps.
    The gunzipped file shows these details on my windows machine,
$ file rEFIt-0.14.cdr
rEFIt-0.14.cdr: Apple Partition data block size: 512,  
first type: Apple_partition_map,  
name: Apple, number of blocks: 63,  
second type: Apple_HFS, name: disk image,  
number of blocks: 40896,
  • Since its a .gz which opened properly for both of us, chances of it being corrupted are none (unless its corrupted at the source).
  • The sourceforege description very clearly says this .cdr should be processed as an ISO. However, this file detail of Apple partition map surprises me a bit. I do not have a Mac handy
    • let me see if I or someone here can figure things out
  • One direction to check is: How to burn a mac-disc on windows?

Oh!, There is something very obvious missing here...
These are bug reports from their sourceforge track!

If your CD recording software refuses to burn the image because of the file extension, rename the file. If it refuses to burn the image because of the file contents, file a bug against the CD recording software.
The distributed image file is a perfectly normal sector-by-sector image like any other "ISO" file. It does not contain an ISO9660 file system; instead it contains an Apple Partition Map and a HFS+ file system. That's what is needed to make Mac systems boot from it.

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Thanks for the answer, but I still can't figure out how to burn a .cdr file. What program should I use? I've tried Nero and AcetonicISO but they didn't recognize this file type. I've also tried to mount the .dmg file under ubuntu, but it gave me some kind of error. – user33684 May 14 '10 at 2:29
thanks again. My hard drive capacity is not big, so I don't want to triple boot. CD burning instructions say "Ask your favourite burning software to burn “rEFIt-0.14.cdr” as a “ISO image” or “disk image”." None of my favorite software recognize a .cdr format. – user33684 May 14 '10 at 2:37
thanks for the update. renaming to iso does not work. But anyway, why why wouldn't the authors of rEFIT make an iso image instead of cdr? – user33684 May 15 '10 at 3:03
Well, I am guessing that the authors made it on a Mac ( – nik May 15 '10 at 3:48

Worked for me on my Ubuntu box: renamed to .iso, then opened K3B, chose 'more options' -> 'burn image' and select the wanted file. First K3B says it's not a valid, but then I chose 'plain data image' on the 'image type' menu on the right and it would just burn it fine! Hope this helps.

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Brasero on ubuntu appears to burn this file properly. As noted by one of the other commentors, this is not a windowsy ISO. Because it doesn't contain an ISO9660 filesystem, many burning software programs complain and even refuse to do anything with it. Brasero on ubuntu worked without a hickup. I simply renamed to .iso, right clicked and selected "Open with Brasero". It then brought up the normal cd/dvd burning dialogue and started burning the DVD. Note that because it's only a few megs, it still has to write a gig or so of data to work properly as a DVD. (I don't have any CDs handy.)

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I was struggling with this problem as well. I got the white screen with blinking grey folder/question mark on my macbook pro a1286 and needed to know whether or not it was the hard drive or logic board that was fried. I run Linux Mint on my lenovo p500 and I needed to burn the refit.014.cdr file to a cd to try and boot from the disk drive to see whether the hard drive was good. I used Archive Manager to extract the cdr.gz file, then selected open with other applications and chose brasero. I changed the file to .iso and it worked perfectly burning to the disk.

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