I'm trying to duplicate a portal before doing some modifications.  I exported the site by using EXPORT PORTAL TEMPLATE and selected with resources.  I then imported it as a child portal and get the error below.  My problem is that after removing the problem portal, I'm now getting this error in my parent portal.  I'm running dnn 4.5.3

DotNetNuke.Services.Exceptions.ModuleLoadException: vbc : Fatal (0): error BC2000: compiler initialization failed unexpectedly: Project already has a reference to assembly DotNetNuke.Caching.FileBasedCachingProvider. A second reference to 'C:\WINDOWS\Microsoft.NET\Framework\V2.0.50727\Temporary ASP.NET Files\root\ffcbecc2\5afe5b69\assembly\dl3\da1a4e43\0e3e5807_95e1c701\DotNetNuke.Caching.FileBasedCachingProvider.DLL' cannot be added. ---> System.Web.HttpCompileException: vbc : Fatal (0): error BC2000: compiler initialization failed unexpectedly: Project already has a reference to assembly DotNetNuke.Caching.FileBasedCachingProvider. A second reference to 'C:\WINDOWS\Microsoft.NET\Framework\V2.0.50727\Temporary ASP.NET Files\root\ffcbecc2\5afe5b69\assembly\dl3\da1a4e43\0e3e5807_95e1c701\DotNetNuke.Caching.FileBasedCachingProvider.DLL' cannot be added. at System.Web.Compilation.AssemblyBuilder.Compile() at System.Web.Compilation.BuildProvidersCompiler.PerformBuild() at System.Web.Compilation.BuildManager.CompileWebFile(VirtualPath virtualPath) at System.Web.Compilation.BuildManager.GetVPathBuildResultInternal(VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.Compilation.BuildManager.GetVPathBuildResultWithNoAssert(HttpContext context, VirtualPath virtualPath, Boolean noBuild, Boolean allowCrossApp, Boolean allowBuildInPrecompile) at System.Web.UI.TemplateControl.LoadControl(VirtualPath virtualPath) at System.Web.UI.TemplateControl.LoadControl(String virtualPath) at DotNetNuke.UI.Skins.Skin.InjectModule(Control objPane, ModuleInfo objModule, PortalSettings PortalSettings) --- End of inner exception stack trace ---