diff --git a/.gitignore b/.gitignore
index 25e7fb9..0cf6cb4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,4 +6,4 @@
 /.vs
 /pdfsign/bin
 /pdfsign/obj
-
+/.idea
diff --git a/pdfsign.sln b/pdfsign.sln
index 082832e..0696bcb 100644
--- a/pdfsign.sln
+++ b/pdfsign.sln
@@ -26,11 +26,13 @@ Global
 		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Debug|Mixed Platforms.Build.0 = Debug|x86
 		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Debug|x86.ActiveCfg = Debug|x86
 		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Debug|x86.Build.0 = Debug|x86
-		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Release|Any CPU.ActiveCfg = Release|x86
 		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Release|Mixed Platforms.ActiveCfg = Release|x86
 		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Release|Mixed Platforms.Build.0 = Release|x86
 		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Release|x86.ActiveCfg = Release|x86
 		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Release|x86.Build.0 = Release|x86
+		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Debug|Any CPU.Build.0 = Debug|x86
+		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{1C38A646-67C2-471B-9951-51ECE43EADC9}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
diff --git a/pdfsign/Properties/AssemblyInfo.cs b/pdfsign/Properties/AssemblyInfo.cs
deleted file mode 100644
index c427562..0000000
--- a/pdfsign/Properties/AssemblyInfo.cs
+++ /dev/null
@@ -1,36 +0,0 @@
-using System.Reflection;
-using System.Runtime.CompilerServices;
-using System.Runtime.InteropServices;
-
-// General Information about an assembly is controlled through the following 
-// set of attributes. Change these attribute values to modify the information
-// associated with an assembly.
-[assembly: AssemblyTitle("pdfsign")]
-[assembly: AssemblyDescription("")]
-[assembly: AssemblyConfiguration("")]
-[assembly: AssemblyCompany("icomedias GmbH")]
-[assembly: AssemblyProduct("pdfsign")]
-[assembly: AssemblyCopyright("Copyright © icomedias GmbH 2019")]
-[assembly: AssemblyTrademark("")]
-[assembly: AssemblyCulture("")]
-
-// Setting ComVisible to false makes the types in this assembly not visible 
-// to COM components.  If you need to access a type in this assembly from 
-// COM, set the ComVisible attribute to true on that type.
-[assembly: ComVisible(false)]
-
-// The following GUID is for the ID of the typelib if this project is exposed to COM
-[assembly: Guid("e40957be-3b89-4869-b337-73e2ff0f24a7")]
-
-// Version information for an assembly consists of the following four values:
-//
-//      Major Version
-//      Minor Version 
-//      Build Number
-//      Revision
-//
-// You can specify all the values or you can default the Build and Revision Numbers 
-// by using the '*' as shown below:
-// [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.3.0.0")]
-[assembly: AssemblyFileVersion("1.3.0.0")]
diff --git a/pdfsign/packages.config b/pdfsign/packages.config
deleted file mode 100644
index 688718c..0000000
--- a/pdfsign/packages.config
+++ /dev/null
@@ -1,5 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<packages>
-  <package id="iTextSharp" version="5.5.13" targetFramework="net40-client" />
-  <package id="Mono.Options" version="5.3.0.1" targetFramework="net40-client" />
-</packages>
\ No newline at end of file
diff --git a/pdfsign/pdfsign.csproj b/pdfsign/pdfsign.csproj
index aed27c5..a7300d2 100644
--- a/pdfsign/pdfsign.csproj
+++ b/pdfsign/pdfsign.csproj
@@ -1,120 +1,17 @@
-<?xml version="1.0" encoding="utf-8"?>
-<Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
-  <PropertyGroup>
-    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
-    <Platform Condition=" '$(Platform)' == '' ">x86</Platform>
-    <ProductVersion>8.0.30703</ProductVersion>
-    <SchemaVersion>2.0</SchemaVersion>
-    <ProjectGuid>{1C38A646-67C2-471B-9951-51ECE43EADC9}</ProjectGuid>
-    <OutputType>Exe</OutputType>
-    <AppDesignerFolder>Properties</AppDesignerFolder>
-    <RootNamespace>pdfsign</RootNamespace>
-    <AssemblyName>pdfsign</AssemblyName>
-    <TargetFrameworkVersion>v4.0</TargetFrameworkVersion>
-    <TargetFrameworkProfile>Client</TargetFrameworkProfile>
-    <FileAlignment>512</FileAlignment>
-    <SccProjectName>SAK</SccProjectName>
-    <SccLocalPath>SAK</SccLocalPath>
-    <SccAuxPath>SAK</SccAuxPath>
-    <SccProvider>SAK</SccProvider>
-    <IsWebBootstrapper>false</IsWebBootstrapper>
-    <PublishUrl>publish\</PublishUrl>
-    <Install>true</Install>
-    <InstallFrom>Disk</InstallFrom>
-    <UpdateEnabled>false</UpdateEnabled>
-    <UpdateMode>Foreground</UpdateMode>
-    <UpdateInterval>7</UpdateInterval>
-    <UpdateIntervalUnits>Days</UpdateIntervalUnits>
-    <UpdatePeriodically>false</UpdatePeriodically>
-    <UpdateRequired>false</UpdateRequired>
-    <MapFileExtensions>true</MapFileExtensions>
-    <ApplicationRevision>0</ApplicationRevision>
-    <ApplicationVersion>1.0.0.%2a</ApplicationVersion>
-    <UseApplicationTrust>false</UseApplicationTrust>
-    <BootstrapperEnabled>true</BootstrapperEnabled>
-  </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Debug|x86' ">
-    <PlatformTarget>x86</PlatformTarget>
-    <DebugSymbols>true</DebugSymbols>
-    <DebugType>full</DebugType>
-    <Optimize>false</Optimize>
-    <OutputPath>bin\Debug\</OutputPath>
-    <DefineConstants>DEBUG;TRACE</DefineConstants>
-    <ErrorReport>prompt</ErrorReport>
-    <WarningLevel>4</WarningLevel>
-    <UseVSHostingProcess>true</UseVSHostingProcess>
-  </PropertyGroup>
-  <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|x86' ">
-    <PlatformTarget>x86</PlatformTarget>
-    <DebugType>pdbonly</DebugType>
-    <Optimize>true</Optimize>
-    <OutputPath>bin\Release\</OutputPath>
-    <DefineConstants>TRACE</DefineConstants>
-    <ErrorReport>prompt</ErrorReport>
-    <WarningLevel>4</WarningLevel>
-  </PropertyGroup>
-  <ItemGroup>
-    <Reference Include="itextsharp, Version=5.5.13.0, Culture=neutral, PublicKeyToken=8354ae6d2174ddca, processorArchitecture=MSIL">
-      <HintPath>..\packages\iTextSharp.5.5.13\lib\itextsharp.dll</HintPath>
-    </Reference>
-    <Reference Include="Mono.Options, Version=5.0.0.0, Culture=neutral, processorArchitecture=MSIL">
-      <HintPath>..\packages\Mono.Options.5.3.0.1\lib\net4-client\Mono.Options.dll</HintPath>
-    </Reference>
-    <Reference Include="System" />
-    <Reference Include="System.Core" />
-    <Reference Include="System.Xml.Linq" />
-    <Reference Include="System.Data.DataSetExtensions" />
-    <Reference Include="Microsoft.CSharp" />
-    <Reference Include="System.Data" />
-    <Reference Include="System.Xml" />
-  </ItemGroup>
-  <ItemGroup>
-    <Compile Include="LTV\AdobeLtvEnabling.cs" />
-    <Compile Include="pdfsign.cs">
-      <SubType>Code</SubType>
-    </Compile>
-    <Compile Include="Properties\AssemblyInfo.cs" />
-  </ItemGroup>
-  <ItemGroup>
-    <BootstrapperPackage Include=".NETFramework,Version=v4.0,Profile=Client">
-      <Visible>False</Visible>
-      <ProductName>Microsoft .NET Framework 4 Client Profile %28x86 and x64%29</ProductName>
-      <Install>true</Install>
-    </BootstrapperPackage>
-    <BootstrapperPackage Include="Microsoft.Net.Client.3.5">
-      <Visible>False</Visible>
-      <ProductName>.NET Framework 3.5 SP1 Client Profile</ProductName>
-      <Install>false</Install>
-    </BootstrapperPackage>
-    <BootstrapperPackage Include="Microsoft.Net.Framework.3.5.SP1">
-      <Visible>False</Visible>
-      <ProductName>.NET Framework 3.5 SP1</ProductName>
-      <Install>false</Install>
-    </BootstrapperPackage>
-    <BootstrapperPackage Include="Microsoft.Windows.Installer.3.1">
-      <Visible>False</Visible>
-      <ProductName>Windows Installer 3.1</ProductName>
-      <Install>true</Install>
-    </BootstrapperPackage>
-  </ItemGroup>
-  <ItemGroup>
-    <None Include="packages.config" />
-  </ItemGroup>
-  <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
-  <PropertyGroup>
-    <PostBuildEvent>rem bitte ilmerge von MS runterladen und installieren http://www.microsoft.com/download/en/details.aspx?displaylang=en&amp;id=17630
-"C:\Program Files (x86)\Microsoft\ILMerge\ILMerge.exe" /wildcards /out:"$(TargetDir)$(TargetName)_merged.exe" "$(TargetPath)" "$(TargetDir)*.dll" /v4
-</PostBuildEvent>
-  </PropertyGroup>
-  <PropertyGroup>
-    <PreBuildEvent>
-    </PreBuildEvent>
-  </PropertyGroup>
-  <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
-       Other similar extension points exist, see Microsoft.Common.targets.
-  <Target Name="BeforeBuild">
-  </Target>
-  <Target Name="AfterBuild">
-  </Target>
-  -->
-</Project>
\ No newline at end of file
+<Project Sdk="Microsoft.NET.Sdk">
+    <PropertyGroup>
+        <OutputType>Exe</OutputType>
+        <RootNamespace>pdfsign</RootNamespace>
+        <TargetFrameworks>net48;net5.0</TargetFrameworks>
+        <AssemblyTitle>pdfsign</AssemblyTitle>
+        <AssemblyCompany>icomedias GmbH</AssemblyCompany>
+        <AssemblyProduct>pdfsign</AssemblyProduct>
+        <AssemblyCopyright>Copyright © icomedias GmbH 2019</AssemblyCopyright>
+        <AssemblyVersion>1.3.0.0</AssemblyVersion>
+        <AssemblyFileVersion>1.3.0.0</AssemblyFileVersion>
+    </PropertyGroup>
+    <ItemGroup>
+        <PackageReference Include="iTextSharp" Version="5.5.13"/>
+        <PackageReference Include="Mono.Options" Version="5.3.0.1"/>
+    </ItemGroup>
+</Project>