diff --git a/tools/mcufontencoder/src/export_bwfont.cc b/tools/mcufontencoder/src/export_bwfont.cc
index 5e9a6779..9b97fb9c 100644
--- a/tools/mcufontencoder/src/export_bwfont.cc
+++ b/tools/mcufontencoder/src/export_bwfont.cc
@@ -22,6 +22,9 @@ static void encode_glyph(const DataFile::glyphentry_t &glyph,
 {
     const int threshold = 8;
     
+    if (glyph.data.size() == 0)
+        return;
+    
     // Find the number of columns in the glyph data
     if (num_cols == 0)
     {
diff --git a/tools/mcufontencoder/src/exporttools.cc b/tools/mcufontencoder/src/exporttools.cc
index b58ee8ec..df7a14c0 100644
--- a/tools/mcufontencoder/src/exporttools.cc
+++ b/tools/mcufontencoder/src/exporttools.cc
@@ -162,6 +162,11 @@ std::vector<char_range_t> compute_char_ranges(const DataFile &datafile,
             if (data_length > maximum_size)
             {
                 last_char = j - 1;
+                
+                // Return the rest of characters to be processed by next range.
+                while (chars.at(i-1) > last_char)
+                    i--;
+                
                 break;
             }
             
diff --git a/tools/mcufontencoder/src/importtools.cc b/tools/mcufontencoder/src/importtools.cc
index c219c207..fdd7108e 100644
--- a/tools/mcufontencoder/src/importtools.cc
+++ b/tools/mcufontencoder/src/importtools.cc
@@ -53,6 +53,9 @@ void crop_glyphs(std::vector<DataFile::glyphentry_t> &glyphtable,
     bbox_t bbox;
     for (DataFile::glyphentry_t &glyph : glyphtable)
     {
+        if (glyph.data.size() == 0)
+            continue; // Dummy glyph
+    
         for (int y = 0; y < fontinfo.max_height; y++)
         {
             for (int x = 0; x < fontinfo.max_width; x++)
@@ -63,12 +66,18 @@ void crop_glyphs(std::vector<DataFile::glyphentry_t> &glyphtable,
         }
     }
     
+    if (bbox.right < bbox.left)
+        return; // There were no glyphs
+    
     // Crop the glyphs to that
     size_t old_w = fontinfo.max_width;
     size_t new_w = bbox.right - bbox.left + 1;
     size_t new_h = bbox.bottom - bbox.top + 1;
     for (DataFile::glyphentry_t &glyph : glyphtable)
     {
+        if (glyph.data.size() == 0)
+            continue; // Dummy glyph
+    
         DataFile::pixels_t old = glyph.data;
         glyph.data.clear();