Make Spotlight show files on unmounted volumes

Though, it won't update the results in spotlight I use the below script to toggle hidden files on and off every time it's run:

To make:

• Open TextEdit
• Make sure it is in Plain Text Mode (Format > Make Plain Text from the menu)
• paste in the below text:

    #Load current state into I
    I=$(defaults read com.apple.Finder AppleShowAllFiles)
    if [ "$I" == "false" ]
      then
        # Flip
        I=true
        echo -e "\t>> Showing Hidden Files"
      else 
        # Flop
        I=false
        echo -e "\t<< Hiding Hidden Files"
    fi
    # Write I to com.apple.Finder.plist
    defaults write com.apple.Finder AppleShowAllFiles $I
    # Restart Finder
    killall Finder
    exit

• Save the above file to your desktop as togglehidden.command (be sure not to append .txt to the end of the file)
• Open /Applications/Utilities/Terminal
• Enter the command chmod u+x ~/Desktop/togglehidden.command to make your new file executable.
• Double Click togglehidden.command on your desktop to show or hide hidden files.

From terminal type:

sudo mdutil -i off [mountpoint]

If you need to remove the index cache of a network drive that has been stored locally, then use the -p flag. Likewise, to remove the local cache of a locally attached volume, use the -E flag.

If you want to delete from /BOOTCAMP then you would use:

sudo mdutil -Ei off "/Volumes/BOOTCAMP"

NOTE: Quotations around the mountpoint of the volume are unnecessary if there are no spaces in the volume name or mountpoint. Otherwise you would need to use an escape character \ before each space.

e.g. sudo mdtuil -Ei off /Volumes/Macintosh\ HD for "Macintosh HD"