diff --git a/SevenZip.Tests/SevenZip.Tests.csproj b/SevenZip.Tests/SevenZip.Tests.csproj
index 06cb59e..74d9685 100644
--- a/SevenZip.Tests/SevenZip.Tests.csproj
+++ b/SevenZip.Tests/SevenZip.Tests.csproj
@@ -10,10 +10,11 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>SevenZip.Tests</RootNamespace>
     <AssemblyName>SevenZip.Tests</AssemblyName>
-    <TargetFrameworkVersion>v4.6.1</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.5</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <NuGetPackageImportStamp>
     </NuGetPackageImportStamp>
+    <TargetFrameworkProfile />
   </PropertyGroup>
   <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|AnyCPU' ">
     <DebugSymbols>true</DebugSymbols>
diff --git a/SevenZip/Formats.cs b/SevenZip/Formats.cs
index 3bd1d8d..74d7d83 100644
--- a/SevenZip/Formats.cs
+++ b/SevenZip/Formats.cs
@@ -370,7 +370,7 @@ internal static int GetMaxValue(Type type)
         /// List of readable archive format interface guids for 7-zip COM interop.
         /// </summary>
         internal static readonly Dictionary<InArchiveFormat, Guid> InFormatGuids =
-            new Dictionary<InArchiveFormat, Guid>(20)
+            new Dictionary<InArchiveFormat, Guid>
             #region InFormatGuids initialization
 
             {
@@ -428,7 +428,7 @@ internal static int GetMaxValue(Type type)
         /// List of writable archive format interface guids for 7-zip COM interop.
         /// </summary>
         internal static readonly Dictionary<OutArchiveFormat, Guid> OutFormatGuids =
-            new Dictionary<OutArchiveFormat, Guid>(2)
+            new Dictionary<OutArchiveFormat, Guid>
             #region OutFormatGuids initialization
 
             {
@@ -443,7 +443,7 @@ internal static int GetMaxValue(Type type)
             #endregion
 
         internal static readonly Dictionary<CompressionMethod, string> MethodNames =
-            new Dictionary<CompressionMethod, string>(6)
+            new Dictionary<CompressionMethod, string>
             #region MethodNames initialization
 
             {
@@ -459,7 +459,7 @@ internal static int GetMaxValue(Type type)
             #endregion
 
         internal static readonly Dictionary<OutArchiveFormat, InArchiveFormat> InForOutFormats =
-            new Dictionary<OutArchiveFormat, InArchiveFormat>(6)
+            new Dictionary<OutArchiveFormat, InArchiveFormat>
             #region InForOutFormats initialization
 
             {
diff --git a/SevenZip/LibraryManager.cs b/SevenZip/LibraryManager.cs
index 14a7338..a9a8812 100644
--- a/SevenZip/LibraryManager.cs
+++ b/SevenZip/LibraryManager.cs
@@ -60,7 +60,7 @@ private static string DetermineLibraryFilePath()
         private static int _totalUsers;
 
         // private static string _LibraryVersion;
-        private static bool? _modifyCapabale;
+        private static bool? _modifyCapable;
 
         private static void InitUserInFormat(object user, InArchiveFormat format)
         {
@@ -151,12 +151,12 @@ public static bool ModifyCapable
             {
                 lock (_syncRoot)
                 {
-                    if (!_modifyCapabale.HasValue)
+                    if (!_modifyCapable.HasValue)
                     {
                         FileVersionInfo dllVersionInfo = FileVersionInfo.GetVersionInfo(_libraryFileName);
-                        _modifyCapabale = dllVersionInfo.FileMajorPart >= 9;
+                        _modifyCapable = dllVersionInfo.FileMajorPart >= 9;
                     }
-                    return _modifyCapabale.Value;
+                    return _modifyCapable.Value;
                 }
             }
         }
diff --git a/SevenZip/SevenZipCompressorAsynchronous.cs b/SevenZip/SevenZipCompressorAsynchronous.cs
index 981375b..5ccd809 100644
--- a/SevenZip/SevenZipCompressorAsynchronous.cs
+++ b/SevenZip/SevenZipCompressorAsynchronous.cs
@@ -2,11 +2,11 @@
 {
     using System.Collections.Generic;
     using System.IO;
-    using System.Threading;
 
     partial class SevenZipCompressor
     {
         #region Delegates
+
         private delegate void CompressFiles1Delegate(string archiveName, string[] fileFullNames);
         private delegate void CompressFiles2Delegate(Stream archiveStream, string[] fileFullNames);
         private delegate void CompressFiles3Delegate(string archiveName, int commonRootLength, string[] fileFullNames);
@@ -17,21 +17,13 @@ partial class SevenZipCompressor
         private delegate void CompressFilesEncrypted3Delegate(string archiveName, int commonRootLength, string password, string[] fileFullNames);
         private delegate void CompressFilesEncrypted4Delegate(Stream archiveStream, int commonRootLength, string password, string[] fileFullNames);
 
-        private delegate void CompressDirectory1Delegate(string directory, string archiveName);
-        private delegate void CompressDirectory2Delegate(string directory, Stream archiveStream);
-        private delegate void CompressDirectory3Delegate(string directory, string archiveName, string password);
-        private delegate void CompressDirectory4Delegate(string directory, Stream archiveStream, string password);
-        private delegate void CompressDirectory5Delegate(string directory, string archiveName,
-            string password, string searchPattern, bool recursion);
-        private delegate void CompressDirectory6Delegate(string directory, Stream archiveStream,
-            string password, string searchPattern, bool recursion);
-
-        private delegate void CompressStream1Delegate(Stream inStream, Stream outStream);
-        private delegate void CompressStream2Delegate(Stream inStream, Stream outStream, string password);
-
-        private delegate void ModifyArchive1Delegate(string archiveName, Dictionary<int, string> newFileNames);
-        private delegate void ModifyArchive2Delegate(string archiveName, Dictionary<int, string> newFileNames,
-             string password);
+        private delegate void CompressDirectoryDelegate(string directory, string archiveName, string password, string searchPattern, bool recursion);
+        private delegate void CompressDirectory2Delegate(string directory, Stream archiveStream, string password, string searchPattern, bool recursion);
+
+        private delegate void CompressStreamDelegate(Stream inStream, Stream outStream, string password);
+
+        private delegate void ModifyArchiveDelegate(string archiveName, IDictionary<int, string> newFileNames, string password);
+
         #endregion
 
         #region CompressFiles overloads
@@ -43,8 +35,7 @@ partial class SevenZipCompressor
         public void BeginCompressFiles(string archiveName, params string[] fileFullNames)
         {
             SaveContext();
-            new CompressFiles1Delegate(CompressFiles).BeginInvoke(archiveName, fileFullNames,
-                AsyncCallbackImplementation, this);
+            new CompressFiles1Delegate(CompressFiles).BeginInvoke(archiveName, fileFullNames, AsyncCallbackImplementation, this);
         }
 
         /// <summary>
@@ -56,22 +47,19 @@ public void BeginCompressFiles(string archiveName, params string[] fileFullNames
         public void BeginCompressFiles(Stream archiveStream, params string[] fileFullNames)
         {
             SaveContext();
-            new CompressFiles2Delegate(CompressFiles).BeginInvoke(archiveStream, fileFullNames,
-                AsyncCallbackImplementation, this);
+            new CompressFiles2Delegate(CompressFiles).BeginInvoke(archiveStream, fileFullNames, AsyncCallbackImplementation, this);
         }
-        
+
         /// <summary>
         /// Packs files into the archive asynchronously.
         /// </summary>
         /// <param name="fileFullNames">Array of file names to pack.</param>
         /// <param name="commonRootLength">The length of the common root of the file names.</param>
         /// <param name="archiveName">The archive file name.</param>
-        public void BeginCompressFiles(
-            string archiveName, int commonRootLength, params string[] fileFullNames)
+        public void BeginCompressFiles(string archiveName, int commonRootLength, params string[] fileFullNames)
         {
             SaveContext();
-            new CompressFiles3Delegate(CompressFiles).BeginInvoke(archiveName, commonRootLength, fileFullNames,
-                AsyncCallbackImplementation, this);
+            new CompressFiles3Delegate(CompressFiles).BeginInvoke(archiveName, commonRootLength, fileFullNames, AsyncCallbackImplementation, this);
         }
 
         /// <summary>
@@ -84,8 +72,7 @@ public void BeginCompressFiles(Stream archiveStream, params string[] fileFullNam
         public void BeginCompressFiles(Stream archiveStream, int commonRootLength, params string[] fileFullNames)
         {
             SaveContext();
-            new CompressFiles4Delegate(CompressFiles).BeginInvoke(archiveStream, commonRootLength, fileFullNames,
-                AsyncCallbackImplementation, this);
+            new CompressFiles4Delegate(CompressFiles).BeginInvoke(archiveStream, commonRootLength, fileFullNames, AsyncCallbackImplementation, this);
         }
 
         /// <summary>
@@ -97,8 +84,7 @@ public void BeginCompressFiles(Stream archiveStream, int commonRootLength, param
         public void BeginCompressFilesEncrypted(string archiveName, string password, params string[] fileFullNames  )
         {
             SaveContext();
-            new CompressFilesEncrypted1Delegate(CompressFilesEncrypted).BeginInvoke(archiveName, password, fileFullNames,
-                AsyncCallbackImplementation, this);
+            new CompressFilesEncrypted1Delegate(CompressFilesEncrypted).BeginInvoke(archiveName, password, fileFullNames, AsyncCallbackImplementation, this);
         }
 
         /// <summary>
@@ -111,8 +97,7 @@ public void BeginCompressFilesEncrypted(string archiveName, string password, par
         public void BeginCompressFilesEncrypted(Stream archiveStream, string password, params string[] fileFullNames)
         {
             SaveContext();
-            new CompressFilesEncrypted2Delegate(CompressFilesEncrypted).BeginInvoke(archiveStream, password, fileFullNames,
-                AsyncCallbackImplementation, this);
+            new CompressFilesEncrypted2Delegate(CompressFilesEncrypted).BeginInvoke(archiveStream, password, fileFullNames, AsyncCallbackImplementation, this);
         }
 
         /// <summary>
@@ -125,8 +110,7 @@ public void BeginCompressFilesEncrypted(Stream archiveStream, string password, p
         public void BeginCompressFilesEncrypted(string archiveName, int commonRootLength, string password, params string[] fileFullNames)
         {
             SaveContext();
-            new CompressFilesEncrypted3Delegate(CompressFilesEncrypted).BeginInvoke(archiveName, commonRootLength, password,
-                fileFullNames, AsyncCallbackImplementation, this);
+            new CompressFilesEncrypted3Delegate(CompressFilesEncrypted).BeginInvoke(archiveName, commonRootLength, password,fileFullNames, AsyncCallbackImplementation, this);
         }
 
         /// <summary>
@@ -140,9 +124,9 @@ public void BeginCompressFilesEncrypted(string archiveName, int commonRootLength
         public void BeginCompressFilesEncrypted(Stream archiveStream, int commonRootLength, string password, params string[] fileFullNames)
         {
             SaveContext();
-            new CompressFilesEncrypted4Delegate(CompressFilesEncrypted).BeginInvoke(archiveStream, commonRootLength, password,
-                fileFullNames, AsyncCallbackImplementation, this);
+            new CompressFilesEncrypted4Delegate(CompressFilesEncrypted).BeginInvoke(archiveStream, commonRootLength, password, fileFullNames, AsyncCallbackImplementation, this);
         }
+
         #endregion
 
         #region BeginCompressDirectory overloads
@@ -155,12 +139,10 @@ public void BeginCompressFilesEncrypted(Stream archiveStream, int commonRootLeng
         /// <param name="password">The archive password.</param>
         /// <param name="searchPattern">Search string, such as "*.txt".</param>
         /// <param name="recursion">If true, files will be searched for recursively; otherwise, not.</param>
-        public void BeginCompressDirectory(string directory, string archiveName,
-            string password = "", string searchPattern = "*", bool recursion = true)
+        public void BeginCompressDirectory(string directory, string archiveName, string password = "", string searchPattern = "*", bool recursion = true)
         {
             SaveContext();
-            new CompressDirectory5Delegate(CompressDirectory).BeginInvoke(directory, archiveName,
-                password, searchPattern, recursion, AsyncCallbackImplementation, this);
+            new CompressDirectoryDelegate(CompressDirectory).BeginInvoke(directory, archiveName, password, searchPattern, recursion, AsyncCallbackImplementation, this);
         }
 
         /// <summary>
@@ -172,14 +154,13 @@ public void BeginCompressFilesEncrypted(Stream archiveStream, int commonRootLeng
         /// <param name="password">The archive password.</param>
         /// <param name="searchPattern">Search string, such as "*.txt".</param>
         /// <param name="recursion">If true, files will be searched for recursively; otherwise, not.</param>
-        public void BeginCompressDirectory(string directory, Stream archiveStream,
-            string password , string searchPattern = "*", bool recursion = true)
+        public void BeginCompressDirectory(string directory, Stream archiveStream, string password , string searchPattern = "*", bool recursion = true)
         {
             SaveContext();
-            new CompressDirectory6Delegate(CompressDirectory).BeginInvoke(directory, archiveStream,
-                password, searchPattern, recursion, AsyncCallbackImplementation, this);
+            new CompressDirectory2Delegate(CompressDirectory).BeginInvoke(directory, archiveStream, password, searchPattern, recursion, AsyncCallbackImplementation, this);
         }
-#endregion
+
+        #endregion
 
         #region BeginCompressStream overloads
 
@@ -193,11 +174,11 @@ public void BeginCompressFilesEncrypted(Stream archiveStream, int commonRootLeng
         public void BeginCompressStream(Stream inStream, Stream outStream, string password = "")
         {
             SaveContext();
-            (new CompressStream2Delegate(CompressStream)).BeginInvoke(inStream, outStream, password, AsyncCallbackImplementation, this);            
+            new CompressStreamDelegate(CompressStream).BeginInvoke(inStream, outStream, password, AsyncCallbackImplementation, this);            
 
         }
         #endregion
-        
+
         #region BeginModifyArchive overloads
 
         /// <summary>
@@ -206,11 +187,10 @@ public void BeginCompressStream(Stream inStream, Stream outStream, string passwo
         /// <param name="archiveName">The archive file name.</param>
         /// <param name="newFileNames">New file names. Null value to delete the corresponding index.</param>
         /// <param name="password">The archive password.</param>
-        public void BeginModifyArchive(string archiveName, Dictionary<int, string> newFileNames,
-            string password = "")
+        public void BeginModifyArchive(string archiveName, IDictionary<int, string> newFileNames, string password = "")
         {
             SaveContext();
-            new ModifyArchive2Delegate(ModifyArchive).BeginInvoke(archiveName, newFileNames, password, AsyncCallbackImplementation, this);
+            new ModifyArchiveDelegate(ModifyArchive).BeginInvoke(archiveName, newFileNames, password, AsyncCallbackImplementation, this);
         }
 
         #endregion
diff --git a/SevenZip/SevenZipSfx.cs b/SevenZip/SevenZipSfx.cs
index 14e03f1..78fcfd0 100644
--- a/SevenZip/SevenZipSfx.cs
+++ b/SevenZip/SevenZipSfx.cs
@@ -47,7 +47,7 @@ public class SevenZipSfx
         {
             get
             {
-                var result = new Dictionary<SfxModule, List<string>>(3)
+                var result = new Dictionary<SfxModule, List<string>>
                 {
                     {SfxModule.Simple, new List<string>(2) {"7z.sfx", "7zCon.sfx"}},
                     {SfxModule.Installer, new List<string>(2) {"7zS.sfx", "7zSD.sfx"}}
@@ -89,8 +89,9 @@ public SevenZipSfx(SfxModule module)
         {
             if (module == SfxModule.Custom)
             {
-                throw new ArgumentException("You must specify the custom module executable.", "module");
+                throw new ArgumentException("You must specify the custom module executable.", nameof(module));
             }
+
             _module = module;
             CommonInit();
         }
diff --git a/SevenZip/StreamWrappers.cs b/SevenZip/StreamWrappers.cs
index d7e6f7c..2bb9a4e 100644
--- a/SevenZip/StreamWrappers.cs
+++ b/SevenZip/StreamWrappers.cs
@@ -230,8 +230,7 @@ private void OnBytesWritten(IntEventArgs e)
     /// </summary>
     internal class MultiStreamWrapper : DisposeVariableWrapper, IDisposable
     {
-        protected readonly Dictionary<int, KeyValuePair<long, long>> StreamOffsets =
-            new Dictionary<int, KeyValuePair<long, long>>();
+        protected readonly Dictionary<int, KeyValuePair<long, long>> StreamOffsets = new Dictionary<int, KeyValuePair<long, long>>();
 
         protected readonly List<Stream> Streams = new List<Stream>();
         protected int CurrentStream;