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The concept seems simple: take a system image of one machine, restore it to another, and avoid lengthy setup time. Unfortunately, it's not that simple.

If I want to install a computer backup from a previous computer, complete with its operating system, onto another computer with a different operating system, will the operating system on the backup be allowed to install and override the operating system on the other computer? If so, how do I get around this?

It's not a question of allowing. By definition, restoring a full image backup will completely overwrite everything that exists on the hard disk, replacing whatever was there before.

So, sure, the previous operating system, along with everything else on the hard disk, will be overwritten and replaced with the contents of the image backup.

The real question is: will what you've just restored then work?

Most of time, the answer is a resounding no.

What's In Your Operating System Installation

When you install an operating system such as Windows, the setup program goes through what appears to be pretty much the same sequence of events that it does on every machine: you enter the product key, type in a little information, tell it what machine name you want and perhaps the time zone, and pick an administrator password. Then, the setup goes to work, showing a progress bar or some propagandainformation about the benefits of the operating system you're installing and how wonderful your life together will be.

What happens behind the scenes is significantly more complex.

Almost every machine is different, and it's during Windows installation time that those differences are accounted for.

"If those conditions are met, then maybe it'll work. And it's a huge if."

The Windows installation media contains software for hundreds if not thousands of different pieces of hardware that can be used with Windows. Only the software that applies to your specific machine is installed.

Windows Setup is as much a customization process as it is an installation process.

If your machine came with Windows pre-installed, this still holds true; it just all happened before you received your computer.

What's In A Backup

Let's start with a quick clarification. For purposes of this discussion, people tend to think of two types of backups: data and full.

A data backup is just that - a backup of your data and for the most part only your data. An example might be burning a copy of all your digital photographs to a couple of CDs for safekeeping.

A full backup also lives up to its name: it's a backup of everything. Typically creating what's called a "system image", this type of backup contains everything on the disk including not only your data, but your programs and Windows itself. A true system image can be restored to an empty hard disk on the same machine on which the backup was originally taken.

A full backup, then, contains your Windows installation, including all of the customizations that were made at setup time.

And that's where restoring to a different machine starts to fall apart.

Restoring to a Different Machine

If you take a backup image from machine A, and restore it to a different machine B it's extremely unlikely to work.

The problem is that all of those customizations that happened at setup time on machine A won't apply to machine B. The drivers installed for hardware on machine A that are not present on machine B will fail, and hardware that's present on machine B won't have the required drivers needed.

Given the incredible complexity of the hardware combinations possible with Windows, it's just not very likely that the scenario will work at all. Typically, the machine will simply and completely fail to boot at all.

Restoring to a Different Machine Can Work If....

It is possible for the scenario to work, but there are several conditions that must be met.

  • The motherboard on machine B must be similar to that of machine A. What does "similar to" mean? There's no real definition: motherboards often have a variety of hardware included that would require a specific set of software drivers in order to work properly. Ideally, the motherboards would be identical.

  • For those individual devices that are not identical, those on machine B must be similar to the devices that they are equivalent to on machine A. Once again, the degree of similarity depends on the specific device and the capabilities of the driver installed on machine A.

  • For those individual devices that are not even similar, then they must be optional, meaning that the system will run properly without the device.

If those conditions are met, then maybe it'll work. And it's a huge if.

It's possible that Windows will be able to boot and that it may then notice that some non-critical hardware has "changed" and go through the process of updating itself, perhaps asking for driver or installation disks, and actually run.

It's actually a very common approach to installations that have a large number of identical machines, but the further you stray from truly identical machines, the lower your chances are of this approach working.

The More Common Alternative

Just because you can't restore and boot from this backup image doesn't mean that the information in that image is lost.

One recovery method is actually quite simple:

  • Install Windows and whatever else you want from scratch onto your new or replacement machine (machine B, to use the terminology above).

  • Restore your backup image to a second hard drive that is not used for booting and access all of the data from there.

In fact, that last step is even optional. Many backup programs will allow you to browse and extract files from system images. You need not actually restore the entire image at all. Just find what you need and copying it out of the image.

Article C4751 - February 26, 2011 « »

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Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

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20 Comments
Thomas Mitchell
February 26, 2011 5:16 PM

Great info thanks, (propaganda) hahahaha (lmao).

Brad-Lee LaDawg
March 1, 2011 8:17 AM

Hey Leo. Your info is not exactly correct. If you use good commercial-quality drive imaging software, most today have an option to restore on a different machine. It'll bypass the machine-specific stuff , load generic drivers, etc. . In my experience it has worked better than 80% of the time - of course there is a lot of tweaking and clean up afterwards. But if you don't have the physical media for your applications, it's sometimes your only choice

Tahoe Joe
March 1, 2011 8:17 AM

I've done this successfully on two different models of Dell machines running xp. My Older Dell 2300 had a number of problems and I didn't want to go through the headaches of reinstalling XP and all my programs and then all the updates. I also had a Dell 2400, with a different motherboard, but had most of the programs I needed and was running well. I used an Acronis Image of the 2400 and restored it to the 2300. After rebooting and finding most of the right drivers automatically, with very little work on my part, the Dell 2300 was up and running in a lot less time than reinstalling XP.

Jim H
March 1, 2011 8:28 AM

Acronis True Image has an addon purchased separately that allows a backup to be restored to a different hardware configuration. So, if you do a restoration with a larger hard drive or to a new PC it is supposed to work. I haven't tried it yet to be honest.

Paul
March 1, 2011 9:11 AM

I use Synchtoy to do a complete back up of Drive C to an external drive. I have wondered long about what is the point of a complete backup? There are always system files in use which fail in the back-up procedure. In the event of needing to restore the entire disk well, it still would not work because of the missing system files. So again what is the point of a back-up? (Yes for data I agree)

Actual backup software can copy most files in use. File copying utilities such as SyncToy, of course, cannot. A couple of additional articles on the topic: What's the difference between disk imaging and copying? Can't I just copy everything instead of using a backup program?
Leo
04-Mar-2011

Jim W
March 1, 2011 9:40 AM

A free download of a program named "Easy Transfer" from Microsoft can help transfer your data and settings if you're doing a clean install upgrade from XP or Vista to Windows 7. Note that if you're upgrading from Vista Premium to Windows 7 premium you can do an "in place" upgrade leaving all your data and programs inplace BUT if you are upgrading from Vista Home Premium to Window 7 Pro (or higher) you will have wipe your hard drive and do a clean install (you won't find this information on the Windows 7 Pro box). The "Easy Transfer" program can be a big help in this case. You can find it and information about it at http://windows.microsoft.com/en-us/windows7/products/features/windows-easy-transfer

Jim Johnson
March 1, 2011 11:50 AM

My understanding is that Microsoft will not allow you to install the same copy of the Windows operating system on more than one computer. If the second computer has a significant number of different components (e.g., mobo or CPU) the installation will not succeed. Please correct me if I'm wrong. It would certainly make my life a lot easier.

Thanks

Jim H
March 1, 2011 1:08 PM

RE: the Microsoft installation. I got the lockout trigger once when I installed a copy of XP pro upgrade on a laptop with XP home because the hardware signature was so different. It was originally on my desktop. I had bought a full version of XP pro for the desk top so wanted to upgrade the version on the other PC to pro as well. Per the message I had to call Microsoft. I did and explained to them I had bought an additional copy of XP and had moved the upgrade to the laptop. I told them it was only installed on one machine. They were very nice -not third degree or treating me like I was a criminal- and from beginning to end I was up and running in under 10 minutes.

ron
March 1, 2011 1:15 PM

I have used the Paragon app that allows restoration to different hardware (it replaces the inappropriate drivers with correct ones), but the sticky wicket is that the restoration will have to be re-activated once it is up and running. The original installation cannot legally be run once the new one is activated.

Vic
March 1, 2011 2:41 PM

Another way to do this successfully is by doing a repair install of Windows after copying the backup to a new drive. I've done this for friends on many occasions and only rarely has it not worked.

An interesting approach. I like it as something to try when this is neccessary.
Leo
04-Mar-2011

narumanchianji
March 2, 2011 7:59 PM

it is possible to restore a full backup on a different computer.1.restore full backup. dont boot the system now. 2. insert original windows cd and start. accept first option to install.3.reject option to repair from console and continue 4.when repair option is offered accept.allow windows to complete the installation and allow to finallyy boot.5.now run the original motherboard drivercd of this new machine.6. if necessary reinstall or renter serial numbers of some applications if they demand(some antivirus may ask for reentering serial number.
that is it. the machine should now work almost perfectly. if required sort out minor problems like vga drivers etc.

Tom
March 4, 2011 4:54 PM

I was under the impression that some programs like Shadow Protect provide for Hardware Independant Restore. Different Companies use different terms for this but there are several out there. Are you saying that these won't work?

I'm getting more reports that these tools may indeed provide a path - albeit a sometimes complicated path - that may frequently work. It's not something I'd like to rely on, but if you're in this position they're worth investigating.
Leo
04-Mar-2011

Anthony P.
March 6, 2011 10:12 PM

I really don't need to avoid any lengthy setup time on any of my machines. Installing Ubuntu usually takes under 15-20 mins, partitioning and all. I'd like to see a few intro to linux articles on this site.

Carlos R Coquet
March 8, 2011 10:20 PM

Actually, plug ‘n' play systems are supposed to be able to adapt to new hardware and, in fact, that is precisely what Windows used to do thru version 98. You could actually replace the motherboard or move the hard disk from one machine to another and Windows would "discover" the new hardware as it came up and, at worst, it would ask for its installation CD to copy the necessary drivers to the machine's hard disk. (Moreover, if you had copied the "I386" directory to the hard disk and "adjusted" the Registry, it would not even ask for the CD.)


Naturally, this was not good for Microsoft and that is probably why they stopped that "convenience" after Windows 98. Generally, if you replace the motherboard in a machine with Windows 2000 or later, Windows will blow up while it boots. And yes, as someone else pointed out, you can boot from the Windows installation CD and run a "repair" operation on the existing \Windows directory and everything will be well. Almost everything. Some software will not. AVG, for example, will not run after a "repair" operation.

Chris
October 25, 2011 2:18 PM

I seem to have managed this trick. I was given two computers, one made by Tiny & the other an old Acer. The tiny pc was full of infections & almost unusable. I took the hard drive from that & scanned it with my av in another machine. (My pc decided it would change the boot sequence to the added drive). Thats not good when its got viruses but i knew from past experience that would happen & went into the bios & changed it back before it got the chance to boot from it. So i got rid of all the infections found & put the drive back into the Tiny pc. It was better but blue screened every now & then. I discovered the Joys of the i386 folder & re-installed. Its seems ok now.

And the other pc was given to me without a hard drive. It did have the xp home serial number on it though. Trying the i386 instal failed because it asked for a service pack two disc. I tried making one & got no where. So then i put an image of the Tiny pc on another drive & put that in the acer machine. I let it boot into safe mode, after some time it discovered new hardware & installed that. After re-starting everything in device manager was ok except for the audio. I thought that was strange because the ac97 drivers used in the Tiny pc worked just fine when i told windows where to look. Also activation worked fine for me too because i had the correct serial number for both sets of hardware.

sandip
August 31, 2012 4:25 AM

I have an hp laptop. All i need to do is upgrade it from vista home premium to windows 7 but then the c drive will be formatted and i will lose everything. So, if I backup the drive first and then install windows 7, will the backup work on the new operating system? Keep in mind that I have some original registered softwares like office 2003 and I want all these softwares back as they were last time. Please someone help me with this if you can (my laptop turned super slow with vista).

Mark J
August 31, 2012 8:08 AM

@Sandip
You wouldn't be able to restore your programs from a backup drive. It is possible, however, to do an upgrade from Vista to Windows 7 which preserves your installed programs. A backup is still a very good idea as sometimes there are problems with an OS upgrade

sandip
October 3, 2012 7:58 AM

@ Mark J
Yes, it is possible and i now believe it will work just the way i want. I installed a program from the microsoft website which detect other applications installed on the system and state whether they are compatible with windows 7 ultimate or not. Only some useless programs will not work, otherwise the upgrade will be very successful. Thanks a lot.

sandip
October 3, 2012 8:04 AM

@ Mark J
Thanks it worked well.

Dennis
March 1, 2013 9:38 AM

I have a backup aimersoft dvd ripper cd which I bought together with online download. can I install that backup cd on a different computetr

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