How to create ISO image file of Windows 7 OS

I have Windows 7 professional OS install in DELL computer including various important application. I would like to create a backup ISO image of existing computer and it has to be bootable one. The size of drive c: is about 90 GB. I know how RUFUS software can make bootable ISO on USB, but I do not know how to create ISO image file of entire Windows 7 OS. Can any one highlight the detail step....?
 
I don't think you can make a bootable ISO of an installed OS. You can use imaging software, something like macrium reflect which is free and decent, to make an image of the HDD. You can also make a bootable version of the program in the event you need to restore a backup after a system failure or whatever.

There's also a backup and restore function in windows, but it's not that great.
 
I don't think you can make a bootable ISO of an installed OS.
Not discounting your reply, which I agree with, this is just for some additional information that may or may not help OP, but might help someone that could stumble across this thread in a web search.

This isn't really an .iso, nor bootable (well depends on your definition), but there is a way to make a virtual machine image from your current real machine's installation: http://www.techrepublic.com/blog/wi...a-working-windows-installation-with-disk2vhd/
 
I can't help but think this poster is referring to needing , "a restore disc", and any disc imaging program such as "Acronis" should be able to do just that.

My recent "lazy man's strategy", has been to install Windows and all my programs to an old HDD, then use the new drive's (SSD or HDD) proprietary transfer software to install the OS and programs onto the new drive. The "image drive", goes onto the shelf, until it's needed. Obviously you can't do that if you're constantly removing and installing new programs.

But, I don't use any of Windows provided folder for data. That all goes on a separate drive.

I realize my needs are relatively simple, and consequently wouldn't necessarily work for others.

With that said, you need to spring for a quality imaging program, (most often recommended is "Acronis"), and keep your backups up to date.
 
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