diff --git a/Infrastructure/Infrastructure.csproj b/Infrastructure/Infrastructure.csproj
index a68a3688..0788b5b7 100644
--- a/Infrastructure/Infrastructure.csproj
+++ b/Infrastructure/Infrastructure.csproj
@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-      <TargetFrameworks>net5.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(MSBuildVersion)' &gt;= '17.0' ">$(TargetFrameworks);net6.0</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
diff --git a/OpenAuth.App/OpenAuth.App.csproj b/OpenAuth.App/OpenAuth.App.csproj
index ddd84984..facf853e 100644
--- a/OpenAuth.App/OpenAuth.App.csproj
+++ b/OpenAuth.App/OpenAuth.App.csproj
@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-      <TargetFrameworks>net5.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(MSBuildVersion)' &gt;= '17.0' ">$(TargetFrameworks);net6.0</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
diff --git a/OpenAuth.Identity/OpenAuth.IdentityServer.csproj b/OpenAuth.Identity/OpenAuth.IdentityServer.csproj
index 116e0ba5..ab5fdc93 100644
--- a/OpenAuth.Identity/OpenAuth.IdentityServer.csproj
+++ b/OpenAuth.Identity/OpenAuth.IdentityServer.csproj
@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-      <TargetFrameworks>net5.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(MSBuildVersion)' &gt;= '17.0' ">$(TargetFrameworks);net6.0</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
diff --git a/OpenAuth.Mvc/OpenAuth.Mvc.csproj b/OpenAuth.Mvc/OpenAuth.Mvc.csproj
index 3cfd2f4d..91bb8e02 100644
--- a/OpenAuth.Mvc/OpenAuth.Mvc.csproj
+++ b/OpenAuth.Mvc/OpenAuth.Mvc.csproj
@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-      <TargetFrameworks>net5.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(MSBuildVersion)' &gt;= '17.0' ">$(TargetFrameworks);net6.0</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
     <UseRazorBuildServer>false</UseRazorBuildServer>
   </PropertyGroup>
 
diff --git a/OpenAuth.Repository/OpenAuth.Repository.csproj b/OpenAuth.Repository/OpenAuth.Repository.csproj
index 5fde6199..05fff002 100644
--- a/OpenAuth.Repository/OpenAuth.Repository.csproj
+++ b/OpenAuth.Repository/OpenAuth.Repository.csproj
@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-      <TargetFrameworks>net5.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(MSBuildVersion)' &gt;= '17.0' ">$(TargetFrameworks);net6.0</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
diff --git a/OpenAuth.WebApi/OpenAuth.WebApi.csproj b/OpenAuth.WebApi/OpenAuth.WebApi.csproj
index 2c7217b3..4e00f6e5 100644
--- a/OpenAuth.WebApi/OpenAuth.WebApi.csproj
+++ b/OpenAuth.WebApi/OpenAuth.WebApi.csproj
@@ -1,8 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
 
   <PropertyGroup>
-      <TargetFrameworks>net5.0</TargetFrameworks>
-    <TargetFrameworks Condition=" '$(MSBuildVersion)' &gt;= '17.0' ">$(TargetFrameworks);net6.0</TargetFrameworks>
+    <TargetFramework>net6.0</TargetFramework>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
diff --git a/docs/core/faq.md b/docs/core/faq.md
index 27973156..94a1b920 100644
--- a/docs/core/faq.md
+++ b/docs/core/faq.md
@@ -106,3 +106,20 @@ lower_case_table_names=1
 执行添加后，把Id返回给前端界面。详情请参考网友博客：[OpenAuth.net入门【5】——解决添加完数据，在未刷新列表时执行删除，数据未被真正删除的问题](https://www.cnblogs.com/wjx-blog/p/15892811.html)
 
 
+## VS2019打开6.0及以后版本
+
+OpenAuth.Net 6.0默认使用.Net 6.0 SDK，VS2019不支持。如果打开项目需要调整csproj项目文件。如下：
+用记事本等工具，打开`Infrastructure.csproj``OpenAuth.Repository.csproj``OpenAuth.App.csproj``OpenAuth.Mvc.csproj``OpenAuth.WebApi.csproj``OpenAuth.IdentityServer.csproj`，将
+```csharp
+  <PropertyGroup>
+    <TargetFramework>net6.0</TargetFramework>
+  </PropertyGroup>
+```
+调整为
+```csharp
+  <PropertyGroup>
+      <TargetFrameworks>net5.0</TargetFrameworks>
+      <TargetFrameworks Condition=" '$(MSBuildVersion)' &gt;= '17.0' ">$(TargetFrameworks);net6.0</TargetFrameworks>
+  </PropertyGroup>
+```
+