What are system partitions and boot partitions?

System partitions and boot partitions are names for partitions (or volumes) on a hard disk that Windows uses when starting. These terms can be confusing because the system partition actually contains the files used to boot Windows 7, while the boot partition contains the system files. Understanding these concepts is important if your computer is configured in one of the following ways:

The system partition contains the hardware-related files and the Boot folder that tell a computer where to look to start Windows. By default, Windows 7 creates a separate system partition when it's installed from scratch (as opposed to upgraded from a previous version of Windows) on an unpartitioned hard drive. This partition is 100 MB in size.

Windows 7 can help safeguard the system partition by preventing reformatting or deletion of it, and if the system partition is kept separate from a boot partition (as recommended), it will not automatically be assigned a drive letter. This means that the system partition won’t appear in Windows Explorer, which prevents the unintentional use of the system partition.

When you turn on your computer, it uses information stored on the system partition to start up. There's only one system partition on a computer running Windows, even if you have different versions of Windows installed on the same computer. However, non-Windows operating systems use different system files. In a multiboot computer using a non-Windows operating system, its system files are located on its own partition, separate from the Windows system partition.

An additional term, the active partition, describes which system partition (and thus which operating system) your computer uses to start.

A boot partition is a partition that contains Windows operating system files. For example, if you have a multiboot computer that contains Windows Vista on one volume and Windows 7 on another, then each of those volumes are considered boot partitions. For more information about boot partitions, see Create a boot partition.

To identify the system or boot partition

You must be logged on as an administrator to perform these steps.

  1. Open Computer Management by clicking the Start button Picture of the Start button, clicking Control Panel, clicking System and Security, clicking Administrative Tools, and then double-clicking Computer Management. Administrator permission required If you're prompted for an administrator password or confirmation, type the password or provide confirmation.

  2. In the left pane, under Storage, click Disk Management.

  3. In the Status column, the system partition is indicated by (System) and the boot partition is indicated by (Boot).

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