diff --git a/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache b/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
index 8af5250c471..bac6fd02a69 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/ApiClient.mustache
@@ -331,7 +331,7 @@ namespace {{packageName}}.Client
                         {
                             queryParams["{{keyParamName}}"] = apiKeyValue;
                         }{{/isKeyInQuery}}{{/isApiKey}}{{#isBasic}}
-                        if (!String.IsNullOrEmpty(Configuration.Username) && !String.IsNullOrEmpty(Configuration.Password))
+                        if (!String.IsNullOrEmpty(Configuration.Username) || !String.IsNullOrEmpty(Configuration.Password))
                         {
                             headerParams["Authorization"] = "Basic " + Base64Encode(Configuration.Username + ":" + Configuration.Password);
                         }{{/isBasic}}{{#isOAuth}}
diff --git a/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs b/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs
index 05585bff932..5f6ec1cf979 100644
--- a/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs
+++ b/samples/client/petstore/csharp/SwaggerClientTest/SwaggerClientTest.userprefs
@@ -2,7 +2,7 @@
   <MonoDevelop.Ide.Workspace ActiveConfiguration="Debug" />
   <MonoDevelop.Ide.Workbench ActiveDocument="TestPet.cs">
     <Files>
-      <File FileName="TestPet.cs" Line="8" Column="25" />
+      <File FileName="TestPet.cs" Line="12" Column="18" />
     </Files>
     <Pads>
       <Pad Id="MonoDevelop.NUnit.TestPad">
@@ -26,4 +26,4 @@
     <BreakpointStore />
   </MonoDevelop.Ide.DebuggingService.Breakpoints>
   <MonoDevelop.Ide.DebuggingService.PinnedWatches />
-</Properties>
\ No newline at end of file
+</Properties>