When Integrate SSRS Reports in Sharepoint Page go the error "SharePoint 2010: "Session state has been disabled for ASP.NET. The Report Viewer control requires that session state be enabled in local mode"

Web.config

First, you need to edit the web.config file of the SharePoint application. Open your web.config and add the httpModules

In the <system.web> section, find the <httpModules> element and edit it like the following:

<httpModules> <add name = “Session” type=”System.Web.SessionState.SessionStateModule” /></httpModules>

You also need to find the element tag <pages> (also under the <system.web> element) and look for the attribute called enableSessionState and set it to true if it is currently false. Save and close the web.config file.

IIS7

• You should then open the IIS 7 manager, and select your web application.
• Open the modules applet under the IIS section.
• Click “Add Managed Module” in the right hand panel.
• Enter a name for the module, I chose “SessionState”, you can pick what you like, but I suggest something related to session state and then in the lower box, select the entry for:

System.Web.SessionState.SessionStateModule, System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a

Made an IISreset, and test again. you can now add your WebPart Report Viewer control to your site.