Hello and welcome to the forums
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As I see other people are assuming that you're using a *nix system,
you can also create a disk image using Windows.
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(Waits for flames to come in....)
-Start diskmgmt.msc from the Windows Run Command.
-The Virtual Disk Service should open up.
-Now on the strip that lies below the Window border, click "Action->Create VHD"
-You'll see a message asking you the type of disk and size.
-Choose Fixed (Recommended)
-Set the disk size.
-Set the path
-Now you should see a new disk being mounted,
this is the disk that you'll be using.
-Right Click on Square beside the disk that says
'Disk 'N', Unknown, Uninitialized.'
-Click Initialize Disk and select
MBR (since you want this, or GPT) on the dialog box and click ok.
-Once it's initialized right click on the white space that says
'XX MB Unallocated'
-Click '
New Simple Volume'
-A wizard should open up.
-Next
-Set your volume size.
-Next
-Assign a drive letter (recommended), or choose an NTFS folder to mount or do nothing
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.
-Next
-Now choose your file system (NOTE: There are three options: FAT/FAT32/NTFS!) or leave it blank, there are tools to help you format
disk images with other FSes.
-Check Perform Quick format if you want to.
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-Next and finish
-Windows Explorer should open a new instance of Disk Manager that'll tell you that there is a new volume inserted, this isn't really a
device it's a virtual disk (loopback device in Unix terms?)
-If you want to browse around the disk open My Computer browse it......
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-To use the disk after browsing etc, you must unmount it, from the Disk Manager right click the square block, and click Detach VHD.
-Done???
Limitations:
The only 2 major limitations are:
-
Filesystems, Only FAT, FAT32 and NTFS are supported, you may need to use a 3rd party program to format the disk after mounting it.
-
Format, Creates VHD files, which may (?) or may not (?) be supported by some emulators, maybe use QEMU's qemu-img.exe or Virtual Box's VboxManage.exe or even M$'s
open source (true!) vhd tool to convert them to IMG or preferred format.
This worked fine for my OS which uses FAT16 as the root filesystem.
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Btw you can also use WinImage (both free and paid) to browse the disk after unmounting it.