Error but unable test with other addons off

[Nocturna]

I get an error that says it's a Carb error the first time in a Wow session that I zone into a Cataclysm instance. Unfortunately, at that moment in time I'm in a raid or heroic group and don't have time (or, frankly, the inclination) to hold up the group while I zone out, kill all addons but Carb, zone back in and see if I get the error. I just click "whatever" to make it go away. This time I copied it first and after the Heroic I pasted and saved it using Notepad. The error causes no problems or issues other than the annoying error message, and I do NOT get the error on subsequent zone-ins to the same instance that day.

Here's the error message I copied:

Date: 2011-02-23 22:17:34
ID: 1
Error occured in: Global
Count: 1
Message: ..\AddOns\Carbonite\Carbonite.lua line 12351:
   attempt to compare number with nil
Debug:
   (tail call): ?
   [C]: ?
   Carbonite\Carbonite.lua:12351: IBGM()
   Carbonite\Carbonite.lua:1306: OnU()
   Carbonite\Carbonite.lua:21846: MOU()
   Carbonite\Carbonite.lua:11239: NXOnUpdate()
   [string "*:OnUpdate"]:1:
      [string "*:OnUpdate"]:1
AddOns:
  Swatter, v5.9.4961 (WhackyWallaby)
  NPCScan, v4.0.3.6
  NPCScanOverlay, v4.0.3.2
  ACP, v3.3.13 
  ArkInventory, v3.02
  ArkInventoryRules, v
  Atlas, v1.18.2
  AtlasBattlegrounds, v1.18.2
  AtlasDungeonLocs, v1.18.2
  AtlasOutdoorRaids, v1.18.2
  AtlasTransportation, v1.18.2
  AtlasLootLoader, vv6.03.00-beta
  Automaton, v1.3.10
  Babylonian, v5.1.DEV.130
  Carbonite, v4.034
  CarboniteTransfer, v1.01
  Chronos, v2.12
  Configator, v5.1.DEV.278
  DBMBurningCrusade, v
  DBMCore, v
  DebugLib, v5.1.DEV.275
  Decursive, v2.6.0.1
  Dominos, v1.24.1
  DominosCast, v
  DominosXP, v
  Identity, v40000
  Informant, v5.9.4961 (WhackyWallaby)
  MageNuggets, v2.079
  Omen, v3.0.8
  PhanxChat, v4.0.3.120
  Recount, v
  Stubby, v5.9.4961 (WhackyWallaby)
  TipTac, v10.12.05
  TipTacItemRef, v10.12.06
  BlizRuntimeLib_enUS v4.0.6.40000 <us>
  (ck=34a)

I won't bother you guys again with this since I'm unable (or unwilling) to hold up raid and Heroic groups while I spend 20 minutes troubleshooting addon (or game) errors, especially when they don't prevent me from running the instance.

Thanks!

Edit: added code tags to improve readability

[Jigain]

What specific instance were you in?