Trying to upgrading to CMS 6 R2 and getting: You are not authorized to access /PageFiles/!?

Server Error in '/' Application.

You are not authorized to access /PageFiles/

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.UnauthorizedAccessException: You are not authorized to access /PageFiles/

ASP.NET is not authorized to access the requested resource. Consider granting access rights to the resource to the ASP.NET request identity. ASP.NET has a base process identity (typically {MACHINE}\ASPNET on IIS 5 or Network Service on IIS 6 and IIS 7, and the configured application pool identity on IIS 7.5) that is used if the application is not impersonating. If the application is impersonating via <identity impersonate="true"/>, the identity will be the anonymous user (typically IUSR_MACHINENAME) or the authenticated request user.

To grant ASP.NET access to a file, right-click the file in Explorer, choose "Properties" and select the Security tab. Click "Add" to add the appropriate user or group. Highlight the ASP.NET account, and check the boxes for the desired access.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[UnauthorizedAccessException: You are not authorized to access /PageFiles/]

   EPiServer.Web.Hosting.VirtualPathVersioningProvider.GetDirectory(String virtualPath) +547

   EPiServer.Web.Hosting.VirtualPathHandler.InitializeProviders(ProviderSettingsCollection providers, Boolean captureCustomExceptions) +1798

   EPiServer.Web.InitializationModule.InitializeVirtualPathProviders(VirtualPathElement vpElement) +171

   EPiServer.Web.InitializeEngine.Initialize() +516

   EPiServer.Web.InitializationModule.Initialize(EPiServerSection config, Settings settings, ConnectionStringSettingsCollection connectionStringSettings) +2150

   EPiServer.Web.InitializeEngine.Initialize() +516

   EPiServer.Web.InitializationModule.StaticInitialization() +1494

   EPiServer.Web.InitializationModule.Initialize(InitializationEngine context) +46

   EPiServer.Framework.Initialization.InitializationEngine.InitializeModules() +647

   EPiServer.Framework.Initialization.InitializationEngine.Initialize(HostType hostType) +115

   EPiServer.Framework.Initialization.InitializationModule.Initialize(HostType hostType) +199

   EPiServer.Framework.Initialization.InitializationModule.FrameworkInitialization(HostType hostType) +64

   EPiServer.Framework.Initialization.InitializationModule.Application_BeginRequest(Object sender, EventArgs e) +46

   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +80

   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +270

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.225 

<virtualRoles replacePrincipal="true">

  <providers>

    <add name="Administrators" type="EPiServer.Security.WindowsAdministratorsRole, EPiServer" />

    <add name="Everyone" type="EPiServer.Security.EveryoneRole, EPiServer" />

    <add name="Authenticated" type="EPiServer.Security.AuthenticatedRole, EPiServer" />

    <add name="Anonymous" type="EPiServer.Security.AnonymousRole, EPiServer" />

    <add name="Creator" type="EPiServer.Security.CreatorRole, EPiServer" />

    <add roles="WebAdmins, Administrators" mode="Any" name="CmsAdmins" type="EPiServer.Security.MappedRole, EPiServer" />

    <add roles="WebEditors" mode="Any" name="CmsEditors" type="EPiServer.Security.MappedRole, EPiServer" />

  </providers>

</virtualRoles>