diff --git a/modules/swagger-codegen/src/main/resources/csharp/README.md b/modules/swagger-codegen/src/main/resources/csharp/README.md
index 3ce83da957b5..794a7c49b1ba 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/README.md
+++ b/modules/swagger-codegen/src/main/resources/csharp/README.md
@@ -6,12 +6,14 @@
 - [RestSharp] (https://www.nuget.org/packages/RestSharp) - 105.1.0 or later
 - [Json.NET] (https://www.nuget.org/packages/Newtonsoft.Json/) - 7.0.0 or later 
 
-NOTE: The DLLs included in the package may not be the latest version. We recommned using [NuGet] (https://docs.nuget.org/consume/installing-nuget) to obtain the latest version of the packages:
+The DLLs included in the package may not be the latest version. We recommned using [NuGet] (https://docs.nuget.org/consume/installing-nuget) to obtain the latest version of the packages:
 ```
 Install-Package RestSharp
 Install-Package Newtonsoft.Json
 ```
 
+NOTE: RestSharp versions greater than 105.1.0 have a bug which causes file uploads to fail. See [RestSharp#742](https://github.com/restsharp/RestSharp/issues/742)
+
 ## Installation
 Run the following command to generate the DLL
 - [Mac/Linux] compile-mono.sh
diff --git a/modules/swagger-codegen/src/main/resources/csharp/compile-mono.sh.mustache b/modules/swagger-codegen/src/main/resources/csharp/compile-mono.sh.mustache
index 1572c5dff261..b1b0c4f0c73a 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/compile-mono.sh.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/compile-mono.sh.mustache
@@ -8,7 +8,7 @@ mono nuget.exe install vendor/packages.config -o vendor;
 mkdir -p bin;
 
 cp vendor/Newtonsoft.Json.8.0.2/lib/{{targetFrameworkNuget}}/Newtonsoft.Json.dll bin/Newtonsoft.Json.dll;
-cp vendor/RestSharp.105.2.3/lib/{{targetFrameworkNuget}}/RestSharp.dll bin/RestSharp.dll;
+cp vendor/RestSharp.105.1.0/lib/{{targetFrameworkNuget}}/RestSharp.dll bin/RestSharp.dll;
 
 mcs -sdk:${netfx} -r:bin/Newtonsoft.Json.dll,\
 bin/RestSharp.dll,\
diff --git a/modules/swagger-codegen/src/main/resources/csharp/compile.mustache b/modules/swagger-codegen/src/main/resources/csharp/compile.mustache
index 098fddb46434..6014320b2f7a 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/compile.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/compile.mustache
@@ -7,6 +7,6 @@ if not exist ".\nuget.exe" powershell -Command "(new-object System.Net.WebClient
 .\nuget.exe install vendor/packages.config -o vendor
 
 cp vendor/Newtonsoft.Json.8.0.2/lib/{{targetFrameworkNuget}}/Newtonsoft.Json.dll bin/Newtonsoft.Json.dll
-cp vendor/RestSharp.105.2.3/lib/{{targetFrameworkNuget}}/RestSharp.dll bin/RestSharp.dll
+cp vendor/RestSharp.105.1.0/lib/{{targetFrameworkNuget}}/RestSharp.dll bin/RestSharp.dll
 
 %CSCPATH%\csc /reference:bin/Newtonsoft.Json.dll;bin/RestSharp.dll /target:library /out:bin/{{packageName}}.dll /recurse:src\*.cs /doc:bin/{{packageName}}.xml
diff --git a/modules/swagger-codegen/src/main/resources/csharp/packages.config.mustache b/modules/swagger-codegen/src/main/resources/csharp/packages.config.mustache
index 06875810b4a4..bd4428e687e0 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/packages.config.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/packages.config.mustache
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="RestSharp" version="105.2.3" targetFramework="{{targetFrameworkNuget}}" developmentDependency="true" />
+  <package id="RestSharp" version="105.1.0" targetFramework="{{targetFrameworkNuget}}" developmentDependency="true" />
   <package id="Newtonsoft.Json" version="8.0.2" targetFramework="{{targetFrameworkNuget}}" developmentDependency="true" />
 </packages>
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/bin/RestSharp.dll b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/bin/RestSharp.dll
index 533b3cc8a31f..59d82f94198e 100644
Binary files a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/bin/RestSharp.dll and b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/bin/RestSharp.dll differ
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile-mono.sh b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile-mono.sh
index 95245af689dd..d768c892f314 100755
--- a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile-mono.sh
+++ b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile-mono.sh
@@ -8,7 +8,7 @@ mono nuget.exe install vendor/packages.config -o vendor;
 mkdir -p bin;
 
 cp vendor/Newtonsoft.Json.8.0.2/lib/net45/Newtonsoft.Json.dll bin/Newtonsoft.Json.dll;
-cp vendor/RestSharp.105.2.3/lib/net45/RestSharp.dll bin/RestSharp.dll;
+cp vendor/RestSharp.105.1.0/lib/net45/RestSharp.dll bin/RestSharp.dll;
 
 mcs -sdk:${netfx} -r:bin/Newtonsoft.Json.dll,\
 bin/RestSharp.dll,\
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile.bat b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile.bat
index 821c60e8bf0d..27681fc968dd 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile.bat
+++ b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/compile.bat
@@ -1,10 +1,12 @@
 @echo off
+
 SET CSCPATH=%SYSTEMROOT%\Microsoft.NET\Framework\v4.0.30319
 
+
 if not exist ".\nuget.exe" powershell -Command "(new-object System.Net.WebClient).DownloadFile('https://nuget.org/nuget.exe', '.\nuget.exe')"
 .\nuget.exe install vendor/packages.config -o vendor
 
 cp vendor/Newtonsoft.Json.8.0.2/lib/net45/Newtonsoft.Json.dll bin/Newtonsoft.Json.dll
-cp vendor/RestSharp.105.2.3/lib/net45/RestSharp.dll bin/RestSharp.dll
+cp vendor/RestSharp.105.1.0/lib/net45/RestSharp.dll bin/RestSharp.dll
 
 %CSCPATH%\csc /reference:bin/Newtonsoft.Json.dll;bin/RestSharp.dll /target:library /out:bin/IO.Swagger.dll /recurse:src\*.cs /doc:bin/IO.Swagger.xml
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/src/main/csharp/IO/Swagger/Properties/AssemblyInfo.cs b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/src/main/csharp/IO/Swagger/Properties/AssemblyInfo.cs
index 1de9edb2a818..f3b9f7d1d145 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/src/main/csharp/IO/Swagger/Properties/AssemblyInfo.cs
+++ b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/src/main/csharp/IO/Swagger/Properties/AssemblyInfo.cs
@@ -1,6 +1,5 @@
 using System.Reflection;
 using System.Runtime.InteropServices;
-using System.Windows;
 
 // General Information about an assembly is controlled through the following
 // set of attributes. Change these attribute values to modify the information
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/vendor/packages.config b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/vendor/packages.config
index c87bbb79fa67..91f17cd0819d 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/vendor/packages.config
+++ b/samples/client/petstore/csharp/SwaggerClientTest/Lib/SwaggerClient/vendor/packages.config
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="RestSharp" version="105.2.3" targetFramework="net45" developmentDependency="true" />
+  <package id="RestSharp" version="105.1.0" targetFramework="net45" developmentDependency="true" />
   <package id="Newtonsoft.Json" version="8.0.2" targetFramework="net45" developmentDependency="true" />
 </packages>