diff --git a/Jenkinsfile b/Jenkinsfile
index 28f3775..4ccf97f 100644
--- a/Jenkinsfile
+++ b/Jenkinsfile
@@ -10,7 +10,7 @@ pipeline {
       steps {
       /* calcolo numero versione... diverso x branch MASTER/DEVELOP */
       script {
-        withEnv(['NEXT_BUILD_NUMBER=631']) {
+        withEnv(['NEXT_BUILD_NUMBER=633']) {
           // env.versionNumber = VersionNumber(versionNumberString : '3.2.${BUILD_DATE_FORMATTED, "yyMM"}.${BUILDS_ALL_TIME}', projectStartDate : '2006-01-01', skipFailedBuilds: true)
           env.versionNumber = VersionNumber(versionNumberString : '3.2.${BUILD_DATE_FORMATTED, "yyMM"}.${BUILDS_ALL_TIME}', projectStartDate : '2006-01-01', skipFailedBuilds: true, overrideBuildsAllTime: '${NEXT_BUILD_NUMBER}')
             env.APP_NAME = 'SteamWareLib'
diff --git a/SteamWareLib/utils.cs b/SteamWareLib/utils.cs
index 1a491fd..ec951a6 100644
--- a/SteamWareLib/utils.cs
+++ b/SteamWareLib/utils.cs
@@ -1501,7 +1501,7 @@ namespace SteamWare
     public static string EncryptString(string Message, string Passphrase)
     {
       byte[] Results;
-      System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
+      UTF8Encoding UTF8 = new UTF8Encoding();
 
       // Step 1. We hash the passphrase using MD5
       // We use the MD5 hash generator as the result is a 128 bit byte array
@@ -1545,8 +1545,9 @@ namespace SteamWare
     /// <returns></returns>
     public static string DecryptString(string Message, string Passphrase)
     {
-      byte[] Results;
-      System.Text.UTF8Encoding UTF8 = new System.Text.UTF8Encoding();
+      string answ = Message;
+      byte[] Results = null;
+      UTF8Encoding UTF8 = new UTF8Encoding();
 
       // Step 1. We hash the passphrase using MD5
       // We use the MD5 hash generator as the result is a 128 bit byte array
@@ -1564,23 +1565,31 @@ namespace SteamWare
       TDESAlgorithm.Padding = PaddingMode.PKCS7;
 
       // Step 4. Convert the input string to a byte[]
-      byte[] DataToDecrypt = Convert.FromBase64String(Message);
-
-      // Step 5. Attempt to decrypt the string
+      byte[] DataToDecrypt = null;
       try
       {
-        ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
-        Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length);
+        DataToDecrypt = Convert.FromBase64String(Message);
       }
-      finally
+      catch
+      { }
+      if (DataToDecrypt != null)
       {
-        // Clear the TripleDes and Hashprovider services of any sensitive information
-        TDESAlgorithm.Clear();
-        HashProvider.Clear();
+        // Step 5. Attempt to decrypt the string
+        try
+        {
+          ICryptoTransform Decryptor = TDESAlgorithm.CreateDecryptor();
+          Results = Decryptor.TransformFinalBlock(DataToDecrypt, 0, DataToDecrypt.Length);
+        }
+        finally
+        {
+          // Clear the TripleDes and Hashprovider services of any sensitive information
+          TDESAlgorithm.Clear();
+          HashProvider.Clear();
+        }
+        // Step 6. Return the decrypted string in UTF8 format
+        answ = UTF8.GetString(Results);
       }
-
-      // Step 6. Return the decrypted string in UTF8 format
-      return UTF8.GetString(Results);
+      return answ;
     }
 
     /// <summary>