diff --git a/honoka/src/honoka_imengine.cpp b/honoka/src/honoka_imengine.cpp
index 75f3f8b..450966b 100644
--- a/honoka/src/honoka_imengine.cpp
+++ b/honoka/src/honoka_imengine.cpp
@@ -1706,6 +1706,7 @@
     hide_aux_string();
     
     if (m_splitter  && (m_splitter != m_convertor) && (!multi)) {
+        m_convertor->unSelected();
         m_splitter->selected();
         if (!m_splitter->isConnected()) {
             if (!m_splitter->connect()) {
@@ -1724,6 +1725,7 @@
         spsegs = m_splitter->getSegmentList();
         m_splitter->reset();
         m_splitter->unSelected();
+        m_convertor->selected();
         s.clear();
         for(unsigned int i = 0;i < spsegs.size();i ++) s += spsegs[i].getYomi();
     }
@@ -1750,7 +1752,15 @@
         for(unsigned int i = 0;i < spsegs.size();i ++) {
             int bl = spsegs[i].getYomi().length();
             int cl = m_convertor->getResultList(i).Yomi.length();
-            if (bl != cl) m_convertor->resizeRegion(bl - cl);
+            if (bl != cl) {
+                bool t = m_convertor->resizeRegion(bl - cl);
+                if (!t) {
+                    update_aux_string(utf8_mbstowcs(String(_("The error was received from Converter. "))));
+                    m_convertor->reset();
+                    show_aux_string();
+                    return;
+                }
+            }
         }
     }
     
diff --git a/honoka/src/multiconvertor.cpp b/honoka/src/multiconvertor.cpp
index 45bddb3..88896c3 100644
--- a/honoka/src/multiconvertor.cpp
+++ b/honoka/src/multiconvertor.cpp
@@ -227,7 +227,13 @@
             for(unsigned int j = 0;j < texts.size();j ++) {
                 int bl = s[j];
                 int cl = instance->convertors[i]->getResultList(j).Yomi.length();
-                if (bl != cl) instance->convertors[i]->resizeRegion(bl - cl);
+                if (bl != cl) {
+                    bool t = instance->convertors[i]->resizeRegion(bl - cl);
+                    if (!t) {
+                        nuc.insert(instance->convertors[i]);
+                        break;
+                    }
+                }
             }
             instance->convertors[i]->setPos(p);
         }