2x Questie\Modules\QuestieQuest.lua:18: attempt to index global 'QuestieReputation' (a nil value)
Questie\Modules\QuestieQuest.lua:18: in function `Initialize'
...rfaceQuestie\Modules\QuestieEventHandler.lua:27: in function <...rfaceQuestie\Modules\QuestieEventHandler.lua:22>

Locals:
self =

{
1 = "Questie"
2 = {
}
GetQuestLogHashes = defined @Questie\Modules\QuestieQuest.lua:1090
ToggleNotes = defined @Questie\Modules\QuestieQuest.lua:43
AbandonedQuest = defined @Questie\Modules\QuestieQuest.lua:362
CompleteQuest = defined @Questie\Modules\QuestieQuest.lua:339
UnhideQuest = defined @Questie\Modules\QuestieQuest.lua:262
GetAllQuestIdsNoObjectives = defined @Questie\Modules\QuestieQuest.lua:436
Math_random = defined @Questie\Modules\QuestieQuest.lua:829
UpdateObjectiveNotes = defined @Questie\Modules\QuestieQuest.lua:499
Initialize = defined @Questie\Modules\QuestieQuest.lua:13
GetAllLeaderBoardDetails = defined @Questie\Modules\QuestieQuest.lua:1169
ForceToMap = defined @Questie\Modules\QuestieQuest.lua:676
ClearAllNotes = defined @Questie\Modules\QuestieQuest.lua:101
GetAllQuestIds = defined @Questie\Modules\QuestieQuest.lua:411
AcceptQuest = defined @Questie\Modules\QuestieQuest.lua:296
HideQuest = defined @Questie\Modules\QuestieQuest.lua:257
PopulateQuestLogInfo = defined @Questie\Modules\QuestieQuest.lua:886
GetAllQuestObjectives = defined @Questie\Modules\QuestieQuest.lua:907
SmoothReset = defined @Questie\Modules\QuestieQuest.lua:172
ShouldQuestShowObjectives = defined @Questie\Modules\QuestieQuest.lua:455
PopulateObjectiveNotes = defined @Questie\Modules\QuestieQuest.lua:850
UpdateHiddenNotes = defined @Questie\Modules\QuestieQuest.lua:210
AddAllNotes = defined @Questie\Modules\QuestieQuest.lua:141
Math_randomseed = defined @Questie\Modules\QuestieQuest.lua:826
GetRawLeaderBoardDetails = defined @Questie\Modules\QuestieQuest.lua:268
RemoveQuestHash = defined @Questie\Modules\QuestieQuest.lua:1120
CalculateAvailableQuests = defined @Questie\Modules\QuestieQuest.lua:1419
DrawAllAvailableQuests = defined @Questie\Modules\QuestieQuest.lua:1295
CompareQuestHashes = defined @Questie\Modules\QuestieQuest.lua:1125
PopulateObjective = defined @Questie\Modules\QuestieQuest.lua:706
GetCurrentHashes = defined @Questie\Modules\QuestieQuest.lua:1116
isCompleteByQuestId = defined @Questie\Modules\QuestieQuest.lua:476
AddFinisher = defined @Questie\Modules\QuestieQuest.lua:511
AddNewQuestHash = defined @Questie\Modules\QuestieQuest.lua:1109
GetQuestHash = defined @Questie\Modules\QuestieQuest.lua:1078
NotesHidden = false
availableQuests = {
}
IsComplete = defined @Questie\Modules\QuestieQuest.lua:495
_IsCompleteHack = defined @Questie\Modules\QuestieQuest.lua:466
UpdateQuest = defined @Questie\Modules\QuestieQuest.lua:393
Reset = defined @Questie\Modules\QuestieQuest.lua:156
}
(*temporary) = nil
(*temporary) = nil
(*temporary) = 15
(*temporary) = 25
(*temporary) = 1
(*temporary) = 15
(*temporary) = "Defense"
(*temporary) = "attempt to index global 'QuestieReputation' (a nil value)"
_QuestieQuest = {
1 = "Questie"
2 = {
}
IsDoable = defined @Questie\Modules\QuestieQuest.lua:1312
DrawAvailableQuest = defined @Questie\Modules

There is (and has been for quite a few updates) only one Questie folder and I did restart WoW after the update (actually, WoW was not running when the update happened).

Therefore, your assumptions used to close this issue were incorrect. I'll open another issue if it still happens.