Win 7/64 pro "Reserved partition" question

Discussion in 'Windows 64bit' started by Sardine, Dec 29, 2009.

  1. Sardine

    Sardine Guest

    My installed W7 has its active booting partition be a small 100 MB
    partition that has no drive letter assigned, it is called "reserved".
    I'm told that if I had installed to a formatted drive, this small
    partition would not exist.

    I'd like to get rid of it and have W7 boot right to the C: system partition.

    In doing some fiddling with ShadowProtect Inage Backup I managed to
    eliminate the small partition and now I boot just fine to C: and my "F8"
    function on booting still works fine.

    Am I in a "bad" situation or is this acceptable to keep this way?

    Sardine, Dec 29, 2009
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  2. The 100MB reserved partition is the default structure Microsoft designed
    into Windows 7 when doing a clean install. This was supposed to as a
    security measure to reduce the affect of malware writing to your boot

    The best thing to do is to just ignore it and forget about it.
    Bobby Johnson, Dec 29, 2009
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  3. Sardine

    Jerry Guest

    Jerry, Dec 29, 2009
  4. Sardine

    R. C. White Guest

    Hi, Fungus.

    No, you are not in a "bad" situation. But the way Win7 did it also was not
    a "bad" situation.

    Most users do not understand the "backwards" definitions of "system volume"
    and "boot volume". See KB 314470, "Definitions for system volume and boot
    volume", , for the actual
    meanings, which are opposite to most users' understanding. And look in the
    Status column of Disk Management to see which of your partitions has each of
    those labels.

    Windows has evolved a lot since the days when there was only a single HDD
    with only a single partition that served as BOTH the system and boot
    volumes. The typical system - especially for newbies - is still organized
    the same way. But many users now have multiple HDDs, and each HDD might be
    divided into multiple volumes.

    But the basic boot process hasn't changed through several generations of
    Windows. The BIOS hands control to the System Partition, which contains the
    boot manager, which locates the boot volume, loads Windows from there, and
    turns over control to Windows. Like the letter "Y", the whole system stands
    on a single leg, but can branch to either of two arms, depending on which OS
    the user chooses for the current session. Actually, of course, there can be
    one or more arms. If there is only a single Windows installed, the "Y"
    becomes an "I", but the process still begins with the one leg and then
    branches to the only arm available. That one leg is the System Volume; each
    of the one or more arms is a potential Boot Volume.

    The System Volume is used just once per session and then typically ignored
    until the system is rebooted, so Microsoft tried in Win7 to eliminate SOME
    of the confusion by creating that small partition to hold the few small
    startup files, and did not even assign that partition a "drive" letter to
    keep it from being deleted or used by accident - or by malware; most users
    don't even realize it is there.

    Win7 also continues Vista's practice of assigning the letter C: to its own
    Boot Volume, rather than to the System Partition, as WinXP and prior Windows
    versions did. When installed by booting from the Win7 DVD, Setup does not
    know of any prior drive letter assignments, so it assigns C: to whichever
    partition the user selects to install Win7 - whether that is the first
    partition on the first (or only) HDD, or the 3rd partition on the 4th HDD.
    (When installed by running Setup from the desktop of an existing Windows
    installation, Win7 Setup uses the letters previously assigned by that
    existing Windows.)

    So the hidden partition you saw was "by design" and Win7 should have worked
    very well with it. By eliminating that partition and making another
    partition your system volume, you've changed the location of the bottom leg
    of the "Y" in my illustration, but so long as that leg exists and the BIOS
    can locate it, your system should boot just fine. The only real requirement
    for the system volume is that it be the Active primary partition on the HDD
    designated in the BIOS as the boot device.

    R. C. White, CPA
    San Marcos, TX

    Microsoft Windows MVP
    Windows Live Mail 2009 (14.0.8089.0726) in Win7 Ultimate x64
    R. C. White, Dec 29, 2009
  5. This small reserved partition had another reason for existance as well --
    BitLocker requires a small system partition that is unencrypted. In Vista,
    you had to either manually create this, or use the tool that was provided to
    create it when you enabled BitLocker. In Win7, this is created by default.
    Charlie Russel - MVP, Dec 29, 2009
  6. Sardine

    Sardine Guest

    R.C. : Thank you for the details, you offer a clear picture of the subject.

    Sardine, Dec 29, 2009
  7. Sardine

    Carlos Guest

    And it is also quite handy as a recovery environment.
    Somehow my boot was screwed up when testing a liveCD (Geexbox) and I didn't
    had to resort to my installation DVD.
    The reserved partition software took care of everything and fixed my no-boot
    Carlos, Dec 30, 2009
  8. Yes, that's where the recovery files are. Again, they need to be on a
    non-encrypted partition, and thus reside here for the scenario where
    BitLocker is used on the C: drive.

    It's also a recognition that HDs have gotten very large indeed, and the
    "loss" of a small portion like this doesn't significantly impact the
    effective size.
    Charlie Russel - MVP, Dec 30, 2009
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