diff --git a/src/Speech/Controller/VOICEPEAKEnumerator.cs b/src/Speech/Controller/VOICEPEAKEnumerator.cs
index d9bf66d..c75cda7 100644
--- a/src/Speech/Controller/VOICEPEAKEnumerator.cs
+++ b/src/Speech/Controller/VOICEPEAKEnumerator.cs
@@ -1,9 +1,11 @@
 using Microsoft.Win32;
 using System;
 using System.Collections.Generic;
+using System.ComponentModel;
 using System.Diagnostics;
 using System.IO;
 using System.Linq;
+using System.Runtime.InteropServices;
 using System.Text;
 using System.Threading.Tasks;
 
@@ -25,6 +27,10 @@ public VOICEPEAKEnumerator()
 
         private string[] ExecuteVoicepeak(string args)
         {
+            if (string.IsNullOrEmpty(path))
+            {
+                return new string[0];
+            }
             ProcessStartInfo psInfo = new ProcessStartInfo();
 
             psInfo.FileName = path;
@@ -33,15 +39,29 @@ private string[] ExecuteVoicepeak(string args)
             psInfo.RedirectStandardOutput = true;
             psInfo.Arguments = args;
 
-            using (Process p = Process.Start(psInfo))
+            try
             {
-                // Voicepeakは非同期実行されるのでプロセス終了後に標準出力を取り出す
-                p.WaitForExit(10);
+                using (Process p = Process.Start(psInfo))
+                {
+                    // Voicepeakは非同期実行されるのでプロセス終了後に標準出力を取り出す
+                    p.WaitForExit(10);
 
-                // 行の整形
-                string[] stdout = p.StandardOutput.ReadToEnd().Split('\n');
-                string[] output = stdout.Where(x => x.Trim().Length > 0).Select(x => x.Trim()).ToArray();
-                return output;
+                    // 行の整形
+                    string[] stdout = p.StandardOutput.ReadToEnd().Split('\n');
+                    string[] output = stdout.Where(x => x.Trim().Length > 0).Select(x => x.Trim()).ToArray();
+                    return output;
+                }
+            }
+            catch (Win32Exception e)
+            {
+                int error = Marshal.GetLastWin32Error();
+                switch (error)
+                {
+                    case 2:
+                        // ERROR_FILE_NOT_FOUND
+                        return new string[0];
+                }
+                throw e;
             }
         }