I am now getting this message when I go to host settings:
"Note: You are running on an old version of the .NET Framework. Future upgrades of the DotNetNuke platform will require .NET 3.5 SP1 or later. If you believe you are running .NET 3.5 SP1 already, please check your web.config file and ensure that the 3.5 or above versions of both System.Core and System.Data.Linq are referenced in the assemblies node"

I am running .NET 3.5 SP1.  And, I did this upgrade in the same environments at the beginning of last week and I did not get this message, but now I am.  What could have changed to cause this message to start showing up?

Judy

Thanks for the reply.

Our upgrade path was 4.5.5 to 4.6.2 to 4.9.5 to 5.1.1 to 5.1.4

Our web.config already had the two items you mentioned.  We fixed the problem by restoring the original 4.5.5 on a local copy and used VS 2008 to migrate to .NET 3.5 first (VS2008 prompted for this when we opened it) and then followed the upgrade path again.  This fixed the problem. 

Comparing the two web.configs, we found several differences.  Not sure exactly which ones fixed the problem.  The changes were:

1. Under <system.webServer> <modules>
    Added 
    <remove name="ScriptModule"/> 
    in front of 
    <add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35" preCondition="managedHandler" />

2. Under <system.webServer><handlers>
   Added to the beginning of the section:
    <remove name="WebServiceHandlerFactory-Integrated"/>
    <remove name="ScriptHandlerFactory"/>
    <remove name="ScriptHandlerFactoryAppServices"/>
    <remove name="ScriptResource"/>

 and added to the end of the section:
   <add name="ScriptHandlerFactory" verb="*" path="*.asmx" preCondition="integratedMode" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
   <add name="ScriptHandlerFactoryAppServices" verb="*" path="*_AppService.axd" preCondition="integratedMode" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>
   <add name="ScriptResource" verb="GET,HEAD" path="ScriptResource.axd" preCondition="integratedMode" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35"/>


3. Under <system.web> <compilation> <assemblies>
Added:
    <add assembly="System.Data.Linq, Version=3.5.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089" />


Moving this new web.config to the production server fixed it there too.

Thanks again for your help.

Judy