diff --git a/Pilz.Updating.Client/Utils.cs b/Pilz.Updating.Client/Utils.cs
index 2cb8609..14555f8 100644
--- a/Pilz.Updating.Client/Utils.cs
+++ b/Pilz.Updating.Client/Utils.cs
@@ -23,6 +23,8 @@ public static class Utils
     public static void CopyFile(FileInfo sourceFile, FileInfo destinationFile)
     {
         var triesLeft = 1;
+        var srcFileName = sourceFile.FullName;
+        var destFileName = destinationFile.FullName;
 
         while (triesLeft > 0)
         {
@@ -30,15 +32,15 @@ public static class Utils
 
             try
             {
-                sourceFile.CopyTo(destinationFile.FullName, true);
+                File.Copy(srcFileName, destFileName, true);
             }
             catch (IOException)
             {
-                if (triesLeft == 0 && File.Exists(destinationFile.FullName))
+                if (triesLeft == 0 && File.Exists(destFileName))
                 {
-                    var oldFile = destinationFile.FullName + ".old";
+                    var oldFile = destFileName + ".old";
                     File.Delete(oldFile);
-                    File.Move(destinationFile.FullName, oldFile, true);
+                    File.Move(destFileName, oldFile, true);
                     File.Delete(oldFile);
                     triesLeft++;
                 }