diff --git a/AboutBox1.cs b/AboutBox1.cs
index ae5d3a3..fb0f568 100644
--- a/AboutBox1.cs
+++ b/AboutBox1.cs
@@ -37,7 +37,7 @@ namespace PDF_Merge
                         return titleAttribute.Title;
                     }
                 }
-                return Path.GetFileNameWithoutExtension(Assembly.GetExecutingAssembly().CodeBase);
+                return Path.GetFileNameWithoutExtension(Assembly.GetExecutingAssembly().Location);
             }
         }
 
@@ -45,7 +45,7 @@ namespace PDF_Merge
         {
             get
             {
-                return Assembly.GetExecutingAssembly().GetName().Version.ToString();
+                return Assembly.GetExecutingAssembly()?.GetName()?.Version?.ToString();
             }
         }
 
diff --git a/ConfForm.cs b/ConfForm.cs
index 6e93b70..8e112ee 100644
--- a/ConfForm.cs
+++ b/ConfForm.cs
@@ -17,11 +17,11 @@ namespace PDF_Merge
         {
             InitializeComponent();
 
-            string sourcePath = ConfigurationManager.AppSettings["PDF-Path"];
-            string outputPath = ConfigurationManager.AppSettings["PDF-Output"];
-            string outputName = ConfigurationManager.AppSettings["PDF-Name"];
-            string outputExt = ConfigurationManager.AppSettings["PDF-Extension"];
-            string dateIndex = ConfigurationManager.AppSettings["dateIndex"];
+            string sourcePath = ConfigurationManager.AppSettings["PDF-Path"] ?? "";
+            string outputPath = ConfigurationManager.AppSettings["PDF-Output"] ?? "";
+            string outputName = ConfigurationManager.AppSettings["PDF-Name"] ?? "merged";
+            string outputExt = ConfigurationManager.AppSettings["PDF-Extension"] ?? ".pdf";
+            string dateIndex = ConfigurationManager.AppSettings["dateIndex"] ?? "0";
 
             int dateIndexValue;
 
diff --git a/MainForm.cs b/MainForm.cs
index 6da352e..890bc0d 100644
--- a/MainForm.cs
+++ b/MainForm.cs
@@ -25,7 +25,7 @@ namespace PDF_Merge
         }
         public void SetPathLable()
         {
-            string sourcePath = ConfigurationManager.AppSettings["PDF-Path"];
+            string sourcePath = ConfigurationManager.AppSettings["PDF-Path"] ?? "";
             
             if (sourcePath != null)
             {
diff --git a/MergePDFs.cs b/MergePDFs.cs
index 03ff9e2..d665a07 100644
--- a/MergePDFs.cs
+++ b/MergePDFs.cs
@@ -60,7 +60,7 @@
         }
         public static string[] CollectPdfFiles()
         {
-            string dirPath = ConfigurationManager.AppSettings["PDF-Path"];
+            string dirPath = ConfigurationManager.AppSettings["PDF-Path"] ?? "";
             Console.WriteLine(dirPath);
             string[] pdfFiles = Directory.EnumerateFiles(dirPath, "*.pdf").ToArray();
             Array.Sort(pdfFiles);
@@ -81,7 +81,7 @@
         public static string GetDate()
         {
             DateTime date = DateTime.Now;
-            string dateFormat = ConfigurationManager.AppSettings["dateFormat"];
+            string dateFormat = ConfigurationManager.AppSettings["dateFormat"] ?? "yyyy-MM-dd";
             return date.ToString(dateFormat);
         }
     }