How to Determine What Disk Partition an OS Is On

1. Click on 'Start' or the Windows orb logo on the taskbar at the bottom of the desktop to show the Start menu. Select 'Run' from the menu to open a dialog box. Type 'compmgmt.msc' in the blank field labeled 'Open,' then click the 'OK' button to open the 'Computer Management' utility.
2. Click on the 'Disk Management' folder in the left pane, which will show drives (or 'partitions' or 'volumes') in the right pane.
3. Look at the first row labeled 'Disk.' Look across the row at each letter, e.g., 'C,' 'D' and so forth. Read the details below the letters. If the word 'System' is under the letter, then the Windows operating system resides there. For example, Windows is commonly housed on 'Disk 0' (zero), in the 'C' partition (drive).