diff --git a/11_write_factorytest_by_esptool.sh b/11_write_factorytest_by_esptool.sh
index ecaf751..1177bed 100755
--- a/11_write_factorytest_by_esptool.sh
+++ b/11_write_factorytest_by_esptool.sh
@@ -6,10 +6,10 @@
 BUILD_TOOL=$(lib_get_esptool_command)
 # BUILD_TOOLの文字列の長さが20以上の場合は、終了する
 if [ ${#BUILD_TOOL} -ge 20 ]; then
+    echo $BUILD_TOOL
     echo "==="
-    echo "esptool module is installed"
     echo "Please execute the script again."
-    echo "もう一度実行してください。"
+    echo "(上記のメッセージを確認したあと) もう一度実行してください。"
     echo "==="
     exit 1
 fi
@@ -50,7 +50,7 @@
 echo "Main firmware: $FIRMWARE_PATH"
 
 # Upload the complete firmware using esptool.py
-$BUILD_TOOL --chip esp32 --port "$PORT" --baud 460800 write_flash -z \
+$BUILD_TOOL --chip esp32 --port "$PORT" --baud 460800 write-flash -z \
     0x1000 "$BOOTLOADER_PATH" \
     0x8000 "$PARTITIONS_PATH" \
     0x10000 "$FIRMWARE_PATH"
diff --git a/lib.sh b/lib.sh
index 2d92e3b..7580ba1 100644
--- a/lib.sh
+++ b/lib.sh
@@ -2,23 +2,28 @@
 
 # 
 lib_get_esptool_command() {
-    WIN_PYTHON="py.exe"
+    WIN_PYTHON="python"
     if command -v esptool.py &> /dev/null
     then
         echo "esptool.py"
     else
     if ! command -v $WIN_PYTHON &> /dev/null
     then
+        $WIN_PYTHON
+        echo "エラー：Pythonコマンドを使用するため、まずPythonをインストールしてください。"
+        exit 1
+        return
         echo "esptool.py nor $WIN_PYTHON could not be found. Please install it first."
         exit 1
     else
         # check if esptool is installed as a module
-        if py.exe -m esptool --help &> /dev/null
+        if $WIN_PYTHON -m esptool --help &> /dev/null
         then
             echo "$WIN_PYTHON -m esptool"
             return
         else
-            bash -c "$WIN_PYTHON -m pip install esptool --no-warn-script-location"
+            $WIN_PYTHON -m pip install --upgrade pip
+            $WIN_PYTHON -m pip install esptool --no-warn-script-location
             return
         fi
         echo "$WIN_PYTHON -m esptool"