diff --git a/ModernKeePassLib/Cryptography/ProtectedData.cs b/ModernKeePassLib/Cryptography/ProtectedData.cs
index cf9dcd5..ea2aefd 100644
--- a/ModernKeePassLib/Cryptography/ProtectedData.cs
+++ b/ModernKeePassLib/Cryptography/ProtectedData.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Runtime.InteropServices.WindowsRuntime;
+using System.Threading.Tasks;
 using Windows.Security.Cryptography.DataProtection;
 using Windows.Storage.Streams;
 using ModernKeePassLib.Native;
@@ -8,47 +9,62 @@ namespace ModernKeePassLib.Cryptography
 {
     public static class ProtectedData
     {
-        public static byte[] Protect(byte[] userData, byte[] optionalEntropy, DataProtectionScope scope)
+        public static async Task ProtectStream(byte[] buffer, IOutputStream stream)
         {
-            var provider =
-                new DataProtectionProvider(scope == DataProtectionScope.CurrentUser ? "LOCAL=user" : "LOCAL=machine");
-            // Encode the plaintext input message to a buffer.
-            var buffMsg = userData.AsBuffer();
+            //instantiate a DataProtectionProvider for decryption
+            var dpp = new DataProtectionProvider("LOCAL=user");
 
-            // Encrypt the message.
-            IBuffer buffProtected;
-            try
+            //Open a stream to load data in
+            using (var inputStream = new InMemoryRandomAccessStream())
             {
-                buffProtected = provider.ProtectAsync(buffMsg).GetAwaiter().GetResult();
+                //cteate data writer to write data to the input stream
+                using (var dw = new DataWriter(inputStream))
+                {
+                    //write data to the stream
+                    dw.WriteBuffer(buffer.AsBuffer());
+                    await dw.StoreAsync();
+
+                    //encrypt the intput stream into the file stream
+                    await dpp.ProtectStreamAsync(inputStream.GetInputStreamAt(0),
+                        stream);
+                }
             }
-            catch (Exception e)
-            {
-                throw;
-            }
-            
-            return buffProtected.ToArray();
         }
 
-
-        public static byte[] Unprotect(byte[] userData, byte[] optionalEntropy, DataProtectionScope scope)
+        public static async Task<byte[]> UnprotectStream(IInputStream stream)
         {
-            var provider =
-                new DataProtectionProvider(scope == DataProtectionScope.CurrentUser ? "LOCAL=user" : "LOCAL=machine");
-            // Decode the encrypted input message to a buffer.
-            var buffMsg = userData.AsBuffer();
+            //instantiate a DataProtectionProvider for decryption
+            var dpp = new DataProtectionProvider();
 
-            // Decrypt the message.
-            IBuffer buffUnprotected;
-            try
+            //create a stream to decrypte the data to
+            using (var outputStream = new InMemoryRandomAccessStream())
             {
-                buffUnprotected = provider.UnprotectAsync(buffMsg).GetAwaiter().GetResult();
-            }
-            catch (Exception e)
-            {
-                throw;
-            }
+                //decrypt the data
+                await dpp.UnprotectStreamAsync(stream, outputStream);
 
-            return buffUnprotected.ToArray();
+                //fill the data reader with the content of the outputStream,
+                //but from position 0
+                using (var dr = new DataReader(outputStream.GetInputStreamAt(0)))
+                {
+                    //load data from the stream to the dataReader
+                    await dr.LoadAsync((uint)outputStream.Size);
+
+                    //load the data from the datareader into a buffer
+                    IBuffer data = dr.ReadBuffer((uint)outputStream.Size);
+
+                    return data.ToArray();
+                }
+            }
+        }
+
+        public static byte[] Unprotect(byte[] pbEnc, byte[] mPbOptEnt, DataProtectionScope currentUser)
+        {
+            throw new NotImplementedException();
+        }
+
+        public static byte[] Protect(byte[] pbPlain, byte[] mPbOptEnt, DataProtectionScope currentUser)
+        {
+            throw new NotImplementedException();
         }
     }
 }
diff --git a/ModernKeePassLib/Keys/KcpUserAccount.cs b/ModernKeePassLib/Keys/KcpUserAccount.cs
index 802b503..e63117e 100644
--- a/ModernKeePassLib/Keys/KcpUserAccount.cs
+++ b/ModernKeePassLib/Keys/KcpUserAccount.cs
@@ -20,6 +20,7 @@
 using System;
 using System.Diagnostics;
 using System.IO;
+using System.Runtime.InteropServices.WindowsRuntime;
 using System.Security;
 
 #if ModernKeePassLib
@@ -67,9 +68,9 @@ namespace ModernKeePassLib.Keys
 		{
 			// Test if ProtectedData is supported -- throws an exception
 			// when running on an old system (Windows 98 / ME).
-			byte[] pbDummyData = new byte[128];
+			/*byte[] pbDummyData = new byte[128];
 			ProtectedData.Protect(pbDummyData, m_pbEntropy,
-				DataProtectionScope.CurrentUser);
+				DataProtectionScope.CurrentUser);*/
 
 			byte[] pbKey = LoadUserKey(false);
 			if(pbKey == null) pbKey = CreateUserKey();
@@ -118,18 +119,16 @@ namespace ModernKeePassLib.Keys
 			{
 				string strFilePath = GetUserKeyFilePath(false);
 #if ModernKeePassLib
-			    byte[] pbProtectedKey;
-			    using (var fileStream = StorageFile.GetFileFromPathAsync(strFilePath).GetAwaiter().GetResult()
-			        .OpenStreamForReadAsync().GetAwaiter().GetResult())
+			    var file = StorageFile.GetFileFromPathAsync(strFilePath).GetAwaiter().GetResult();
+			    using (var fileStream = file.OpenReadAsync().GetAwaiter().GetResult())
 			    {
-			        pbProtectedKey = new byte[(int) fileStream.Length];
-			        fileStream.Read(pbProtectedKey, 0, (int) fileStream.Length);
+			        pbKey = ProtectedData.UnprotectStream(fileStream).GetAwaiter().GetResult();
 			    }
 #else
 				byte[] pbProtectedKey = File.ReadAllBytes(strFilePath);
-#endif
-				pbKey = ProtectedData.Unprotect(pbProtectedKey, m_pbEntropy,
+                pbKey = ProtectedData.Unprotect(pbProtectedKey, m_pbEntropy,
 					DataProtectionScope.CurrentUser);
+#endif
 			}
 			catch(Exception)
 			{
@@ -149,19 +148,19 @@ namespace ModernKeePassLib.Keys
 			string strFilePath = GetUserKeyFilePath(true);
 
 			byte[] pbRandomKey = CryptoRandom.Instance.GetRandomBytes(64);
-			byte[] pbProtectedKey = ProtectedData.Protect(pbRandomKey,
-				m_pbEntropy, DataProtectionScope.CurrentUser);
 #if ModernKeePassLib
-		    using (var fileStream = StorageFile.GetFileFromPathAsync(strFilePath).GetAwaiter().GetResult()
-		        .OpenStreamForWriteAsync().GetAwaiter().GetResult())
+		    var file = ApplicationData.Current.RoamingFolder.CreateFileAsync(UserKeyFileName, CreationCollisionOption.ReplaceExisting).GetAwaiter().GetResult();
+		    using (var fileStream = file.OpenAsync(FileAccessMode.ReadWrite).GetAwaiter().GetResult())
 		    {
-		        fileStream.Write(pbProtectedKey, 0, (int) fileStream.Length);
+		        ProtectedData.ProtectStream(pbRandomKey, fileStream).GetAwaiter().GetResult();
 		    }
 #else
+			byte[] pbProtectedKey = ProtectedData.Protect(pbRandomKey,
+				m_pbEntropy, DataProtectionScope.CurrentUser);
 			File.WriteAllBytes(strFilePath, pbProtectedKey);
 #endif
 
-			byte[] pbKey = LoadUserKey(true);
+            byte[] pbKey = LoadUserKey(true);
 			Debug.Assert(MemUtil.ArraysEqual(pbKey, pbRandomKey));
 
 			MemUtil.ZeroByteArray(pbRandomKey);