Hi, i am trying to create an image file of my HDD using the disk utility in recovery mode. I have a 160 GB external hard drive that i would like to save it to. When I attempt to create it, it starts but fails part way through, giving an input/output error. Both the laptop and the external HDD were powered on the entire time. Thanks in advance for any help.
MacBook Air
More information is required - did you receive more than just a generic "I/O error" message - a number, for example? Are you sure the external drive is large enough and has enough space? Have you tried formatting or reparitioning the external drive?
I received a generic error message, with no number. The external is 160 GB, and before i tried to create the .dmg I reformated the drive as MS-DOS (FAT) using the disk utility. I did notice that when I try to create a new disk image from Macintosh HD (my HDD) it gives a "File to large" error, I tried to create a new image from folder, then selected Macintosh HD under devices from the left hand navigation pane. Thanks for your continued help.
You should not have formatted the drive as MS DOS, it should be a GUID partition and formatted as HFS+.
Thanks for your help, it looks like it is working now that I formated it to HFS+
Disk Utility Error (input output error)
