diff --git a/src/slic3r/GUI/DoubleSliderForLayers.cpp b/src/slic3r/GUI/DoubleSliderForLayers.cpp
index 4a56eea221..158629be0c 100644
--- a/src/slic3r/GUI/DoubleSliderForLayers.cpp
+++ b/src/slic3r/GUI/DoubleSliderForLayers.cpp
@@ -1248,6 +1248,9 @@ std::string DSForLayers::get_tooltip(int tick/*=-1*/)
         else if (conflict == ctMeaninglessToolChange)
             tooltip += _u8L("There is an extruder change set to the same extruder.\n"
                            "This code won't be processed during G-code generation.");
+        else if (conflict == ctNotPossibleToolChange)
+            tooltip += _u8L("There is an extruder change set to the not existing extruder.\n"
+                           "This code won't be processed during G-code generation.");
         else if (conflict == ctRedundant)
             tooltip += _u8L("There is a color change for extruder that has not been used before.\n"
                            "Check your settings to avoid redundant color changes.");
diff --git a/src/slic3r/GUI/TickCodesManager.cpp b/src/slic3r/GUI/TickCodesManager.cpp
index b11a409547..d1b681c42a 100644
--- a/src/slic3r/GUI/TickCodesManager.cpp
+++ b/src/slic3r/GUI/TickCodesManager.cpp
@@ -659,6 +659,9 @@ ConflictType TickCodeManager::is_conflict_tick(const TickCode& tick, Mode main_m
         // We should mark a tick as a "MeaninglessToolChange", 
         // if it has a ToolChange to the same extruder
         auto it = ticks.find(tick);
+        if (it->extruder > colors.size())
+            return ctNotPossibleToolChange;
+
         if (it == ticks.begin())
             return tick.extruder == std::max<int>(only_extruder_id, 1) ? ctMeaninglessToolChange : ctNone;
 
@@ -676,6 +679,9 @@ std::string TickCodeManager::get_color_for_tool_change_tick(std::set<TickCode>::
 {
     const int current_extruder = it->extruder == 0 ? std::max<int>(only_extruder_id, 1) : it->extruder;
 
+    if (current_extruder > colors.size())
+        return it->color;
+
     auto it_n = it;
     while (it_n != ticks.begin()) {
         --it_n;
diff --git a/src/slic3r/GUI/TickCodesManager.hpp b/src/slic3r/GUI/TickCodesManager.hpp
index c736545a22..bf440b696a 100644
--- a/src/slic3r/GUI/TickCodesManager.hpp
+++ b/src/slic3r/GUI/TickCodesManager.hpp
@@ -37,6 +37,7 @@ enum ConflictType
     ctModeConflict,
     ctMeaninglessColorChange,
     ctMeaninglessToolChange,
+    ctNotPossibleToolChange,
     ctRedundant
 };