For Plugin Support (bug report, feature request, etc), please use 
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This backpack works with 
TokenEnchant / AutoSell / InventoryFull.  Mined/exploded blocks are automatically stored in the backpack, and AutoSell commands will check contents of backpacks as well as the player inventory!!!  
This plugin provides a virtual backpack. A player can have multiple backpacks.  Each backpack can be accessed through a command or a key item.  You can customise what item to represent a key in config.yml.
Test Server:Commands:  (alias: vkbp, bp, backpack)
- /vkbackpack help : display the help menu.
- /vkbackpack reload : reloads config.yml.
- /vkbackpack give   [backpack_name] : issue a backpack of size  to .
- /vkbackpack open  : opens the backpack called 
- /vkbackpack key  : get a key to open your backpack named as .
- /vkbackpack list : get a list of your backpacks.
- /vkbackpack setmax   : sets the maximum number of backpacks  can have to .
- /vkbackpack rename   : rename the backpack from  to .
- /vkbackpack remove [player]  : throw away  backpack. If [player] is present [player]'s  backpack will be removed.
- /vkbackpack release : flags the backpack to be released/traded.
- /vkbackpack claim : claim the backpack associated with the key you're holding.  If it's someone else's backpack, it will become yours.
- /vkbackpack setsize   : sets the size of the backpack in hand of the player  to ."
Permissions:- vkbackpack.admin : allows you to use reload, give, setmax commands
- vkbackpack.use : allows you to use key, list commands
- vkbackpack.open : allows you to use /bp open command to open a backpack
- vkbackpack.rename : allows you to rename your backpack
- vkbackpack.trade : allows you to use /bp release|claim command to trade your backpack.
- vkbackpack.crafting: allows a player to craft a backpack item.
Installation:Install VKBackPack.jar in the plugins folder.
Work with: 
[dropdown=Sample Config.yml]
[/FONT][/COLOR][/font][/color][/font][/size][/color]
Messages:
  ErrorMsg: "&c [VKBP] : Some error occured : %error%"
  MaxSet: "&a[VKBP] The maxinum number of backpacks &e%player% &acan have is set to &e%number%&a."
  GaveBP: "&a[VKBP] The backpack (name: &e%bpname%&a) of size &e%number% &a was given to &e%player%&a."
  GaveKey: "&a[VKBP] A key for the backpack (name: &e%bpname%&a) is issued."
  Named: "&a[VKBP] A key for the backpack (name: &e%bpname%&a) is issued."
  NoSuchBP: "&a[VKBP] A backpack called &e%bpname%&a was not found in %player%'s list."
  ReNamed: "&a[VKBP] A key was renamed from &e%oldname%&a to &e%newname%&a."
  Maxed: "&c[VKBP] You already maxed out with your backpacks."
  Removed: "&a[VKBP] You've threw away a backpack called &e%bpname%&a."
  NoBP: "&c[VKBP] You cannot hold any backpack."
  Needs9: "&c[VKBP] Backpack size must be multiple of 9."
  Released: "&a[VKBP] You have flagged %bpname% to be claimable backpack."
  Claimed: "&a[VKBP] You have claimed %player%'s backpack named %bpname%."
  InvClear: "&6Cleared all inventory items from %player%."
  NoWorld: "&c[VKBP] You cannot use it in this world (&e%world%&c)."
  NoRegion: "&c[VKBP] You cannot use it in this region (&e%region%&c)."
  SizeChanged: "&a[VKBP] The size of %player%'s backpack (&e%bpname%&a) has been changed to &e%size%&a."
  NoPlayer: "&c[VKBP] There is not such a player (&e%player%&c)."
  NoPerm: "&c[VKBP] You don't have a sufficient permission."
  InvFull: "&c[VKBP] Your backpack %bpname% is full!"
# Customizable help messages
HelpMessages:
  banner:
    msg: "=== &e[&aVKBackPack Commands List (%version%)&e] &r==="
  help:
    msg: "&a/vkbackpack help : display this help menu."
  reload:
    msg: "&a/vkbackpack reload : reloads config.yml."
    permission: "vkbackpack.reload"
  give:
    msg: "&a/vkbackpack give   [backpack_name] : issue a backpack of size  to ."
    permission: "vkbackpack.admin"
  addmax:
    msg: "&a/vkbackpack addmax   : adds the specified number to the maximum number of backpacks  can have."
    permission: "vkbackpack.admin"
  setmax:
    msg: "&a/vkbackpack setmax   : sets the maximum number of backpacks  can have to ."
    permission: "vkbackpack.admin"
  open:
    msg: "&a/vkbackpack open [player]  : opens the backpack called "
    permission: "vkbackpack.open"
  key:
    msg: "&a/vkbackpack key  : get a key to open your backpack named as ."
    permission: "vkbackpack.key"
  list:
    msg: "&a/vkbackpack list [player]: get a list of your backpacks."
    permission: "vkbackpack.use"
  rename:
    msg: "&a/vkbackpack rename  : rename the currently holding backpack to ."
    permission: "vkbackpack.rename"
  remove:
    msg: "&a/vkbackpack remove [player]  : throw away  backpack."
    permission: "vkbackpack.use"
  release:
    msg: "&a/vkbackpack release : releases the backpack represented by the key you're holding."
    permission: "vkbackpack.trade"
  claim:
    msg: "&a/vkbackpack claim : claims the backpack represented by the claimable key you're holding."
    permission: "vkbackpack.trade"
  setsize:
    msg: "&a/vkbackpack setsize   : sets the size of the backpack in hand of the player  to ."
    permission: "vkbackpack.setsize"
# adjust these event priority if those event processes from this plugin
# interfere with other plugins' event processes.
EventPriorityMap:
  BlockBreakEvent: "HIGH"
  PlayerCommandPreprocessEvent: "LOWEST"
# prefix for the name of 4DBackPack inventory
BackPackPrefix: "VKBackPack"
# default number backpacks a player can have.
# if you set '-1' to this option, no max limit will be imposed.
DefaultMaxBackPacks: 3
# if this option is true,  in the "/bp give  "
# is specifed as the number of rows instead of the number of slots.
UseRowAsSize: true
# if VKAutoPickup is installed, this option will be force turned off.
AutoPickUp: true
#
AutoSmelting: true
StoneToStone: true
#
AutoBlocking: true
# if the following flag is true, backpack key will act as a physical
# backpack item.
PhysicalBackpack: true
# if the above option is true, you probably should set the following
# two display flag to "false"
DisplayReleasedMessage: true
DisplayClaimedMessage: true
#
KeyItem: CHEST #TRIPWIRE_HOOK
KeyItemName: "&dBackPack (%bpname%) for %player% (size: %size%)"
KeyItemLore:
  - "&a%bpname% for %player% (%slot%)"
  - "&aClick to open BackPack!"
# if this is "true", a key will be issued upon execution of "give" command.
# this option will not be used if "PhysicalBackpack" option sis true
IssueKeyUponGiveBP: true
# default backpack prefix
BackPackNamePrefix: "BP"
# default name
BackPackDefaultName: "%prefix%[%number%]"
# backpack id prefix.
BackPackIDPrefix: "ID: "
# owner prefix.
BackPackOwnerPrefix: "OWNER: "
# slot prefix.
BackPackSlotsPrefix: "Slots: "
# use its own /ci
UseOwnClearInventory: true
# Disabled Worlds
DisabledWorlds:
  - someworld
# Disabled Regions (WorldGuard regions)
DisabledRegions:
  - someregion
# Backpack listing header format
ListHeader: "=== &e[&aBackPack List&e] &r==="
ListPlayerHeader: "=== &e[&b%player% &acan have up to &b%max% &abackpacks&e] &r==="
ListColumn: "&e  [Name]  ,  [Slot Size]"
# clear inventory commands/aliases
ClearInventoryCommands:
  - ci
  - clean
  - clearinvent
  - clearinventory
#
# Recipe
# if you want a player to craft his/her own IW bucket, you can specify the recipe here
#
EnableCrafting: false
CraftingPrefix: "Crafting"
Recipe:
  vkbp1: #size 1 row
    row: 1
    shape:
      - "M**"
      - "*C*"
      - "***"
    ingredient:
      '*': AIR
      'C': CHEST
      'M': EMERALD
  vkbp2: #size 2 row
    row: 2
    shape:
      - "MM*"
      - "*C*"
      - "***"
    ingredient:
      '*': AIR
      'C': CHEST
      'M': EMERALD
  vkbp3: #size 3 row
    row: 3
    shape:
      - "MMM"
      - "*C*"
      - "***"
    ingredient:
      '*': AIR
      'C': CHEST
      'M': EMERALD
  vkbp4: #size 4 row
    row: 4
    shape:
      - "MMM"
      - "*C*"
      - "M**"
    ingredient:
      '*': AIR
      'C': CHEST
      'M': EMERALD
  vkbp5: #size 5 row
    row: 5
    shape:
      - "MMM"
      - "*C*"
      - "MM*"
    ingredient:
      '*': AIR
      'C': CHEST
      'M': EMERALD
  vkbp6: #size 6 row
    row: 6
    shape:
      - "MMM"
      - "*C*"
      - "MMM"
    ingredient:
      '*': AIR
      'C': CHEST
      'M': EMERALD
[/dropdown]