diff --git a/inferium-harvester.lua b/inferium-harvester.lua
index 9d2fe6f..ab1c0a2 100644
--- a/inferium-harvester.lua
+++ b/inferium-harvester.lua
@@ -3,7 +3,7 @@ local utils = require('libs/utils')
 local inferium = require('libs/inferium')
 local turtleUtils = require('libs/turtle-utils')
 
-local VERSION = "4.1.0"
+local VERSION = "4.1.1"
 local IDLE_TIME = 2
 local WAIT_ITEM_IDLE_TIME = 5
 local NETWORK_TIMEOUT = 4
@@ -440,20 +440,20 @@ local function retrieveFertilizedEssences(_)
   local slot = getItemSlot(storageInventory, inferium.FERTILIZED_ESSENCE)
 
   if slot then
-    local inventoryCount = getCountItem(storageInventory, inferium.FERTILIZED_ESSENCE)
+    local inventoryCount = getCountItem(storageInventory, inferium.FERTILIZED_ESSENCE) or 0
     local realCount = math.min(MAX_FERTILIZED_ESSENCE, inventoryCount)
 
     print('> retrieve ' .. tostring(realCount) .. ' fertilized essences from storage')
     local pushOk = storageInventory.pushItems(peripheral.getName(bufferInventory), slot, realCount)
 
     if not pushOk then
-      error('retrieveFertilizedEssences error: cannot pushItems from storage to buffer')
+      return false
     end
 
     local suckOk = turtle.suck()
 
     if not suckOk then
-      error('retrieveFertilizedEssences error: cannot suck items from buffer')
+      return false
     end
 
     return true