diff --git a/NITBook/packages.config b/NITBook/packages.config
index f28ced8..a563e99 100644
--- a/NITBook/packages.config
+++ b/NITBook/packages.config
@@ -24,7 +24,7 @@
   <package id="Microsoft.jQuery.Unobtrusive.Ajax" version="3.2.6" targetFramework="net452" />
   <package id="Microsoft.jQuery.Unobtrusive.Validation" version="3.2.3" targetFramework="net452" />
   <package id="Microsoft.Net.Compilers" version="1.0.0" targetFramework="net452" developmentDependency="true" />
-  <package id="Microsoft.Owin" version="3.0.1" targetFramework="net452" />
+  <package id="Microsoft.Owin" version="4.0.0" targetFramework="net452" />
   <package id="Microsoft.Owin.Host.SystemWeb" version="3.0.1" targetFramework="net452" />
   <package id="Microsoft.Owin.Host.SystemWeb.zh-Hans" version="3.0.1" targetFramework="net452" />
   <package id="Microsoft.Owin.Security" version="3.0.1" targetFramework="net452" />