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I've got Windows 7 installed and have got Acronis Disk Director. I'm wanting to copy the Windows 7 partition and then use a boot manager to allow me to boot from both Windows 7 copies.

The worry I have is that I know Windows 7 creates a System partition that is 100MB or so for whatever reason, and when I copy the current Windows 7 partition, what (if any) precautions must I take from the point of view of this System Reserved partition, as I'm not looking forward to messing up the original OS.

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The System Reserved partition is a Poor Man's equivalent of a true system volume. It is where Microsoft's Boot Manager and the BCD live. If you have a System Reserved partition then you actually already have a boot manager; and that boot manager is what is currently starting Windows on your system.

By copying around the Windows 7 boot volume, you are just copying around the Windows operating system files and ancillaries, and your applications programs and user data (if they are on the boot volume). If you don't touch the contents of your (Poor Man's) system volume at all, then you won't alter your boot manager.

If you create a duplicate boot volume, then you'll need to tell the boot manager about it, with a new entry for the boot menu. Similarly, if you move a boot partition that's already on the boot menu to a different location, you'll have to tell the boot manager about the new location. Both of these actions involve editing the BCD database with the BCDEdit tool that comes with Windows.

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Hi JdeBP, thanks very much, that's quite a comprehensive answer, I've tried to understand it all, but I've got a couple of further questions. You say If you don't touch the contents of your (Poor Man's) system volume at all, then you won't alter your boot manager. In what ways could I mess with the System Reserved partition? I'm guessing it would have to be assigned a drive letter first? Also, if the System Reserved partition is the boot manager (as opposed to the OS which is the boot volume), then why has the creation of such a partition only started with Windows 7? Thanks. – R4D4 Aug 2 '11 at 11:21
Sorry, one last one... If I'm using my own boot manager then would it still matter if the System Reserved partition is messed up? – R4D4 Aug 2 '11 at 11:31
It has not started with Windows 7. Windows NT has had the notion of distinct system and boot partitions since the days of Windows NT version 3. This is not something new. And yes, assigning it a drive letter and going in and fiddling with things is one way of messing with the contents of one's System Reserved partition. Removing the "startable" attribute is another way. – JdeBP Aug 2 '11 at 11:34
Furthermore, unless your add-on boot manager is capable of directly invoking the Windows NT 6 boot loader (WINLOAD) and resume loader (WINRESUME), you'll still be using Microsoft's Boot Manager and the accompanying BCD database at some point in the bootstrap process. – JdeBP Aug 2 '11 at 11:39

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