The DISKQUOTA REBUILD command reads the disk, recalculates
    usage counts for all existing entries in QUOTA.SYS, and adds
    new entries. It sets quota and overdraft values to the defaults
    set in UIC [0,0] if the entry did not previously exist. While
    the DISKQUOTA REBUILD command is executing, file activity on the
    volume is frozen. No files can be created, deleted, extended, or
    truncated.

    Use the DISKQUOTA REBUILD command in the following circumstances:

    o  After creating a quota file on a volume with existing files.

    o  When the quota file has been enabled after a period of being
       disabled. The command corrects the usage counts and adds any
       new UICs.