Session state cannot be used in ASP.NET with Windows SharePoint Services

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Add the following directives in the Web.config file of the Web application between the <system.web> tag and the </system.web> tag:


<!--
Clear out the WSS ASP.NET handler and specify the default ASP.NET handler for all pages.
-->

<httpHandlers>
<clear />
<add verb="*" path="*.aspx" type="System.Web.UI.PageHandlerFactory, System.Web,
Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
</httpHandlers>

<!--
Set the trust to Full. WSS configures a very restrictive trust policy that does not
allow ASP.NET Web application to run correctly.
-->

<trust level="Full" originUrl="" />

<!--
Enable the session module. This can also be enabled on the WSS Web.config,
but is not enabled by default. If you receive the following message:
Parser Error Message: The module 'Session' is already in the application
and cannot be added again. You can remove the following
<httpModules></httpModules> section as session is already enabled
on the virtual server.
-->

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

<!-- Enable session state for all the pages in the Web application. -->
<pages enableSessionState="true" enableViewState="true"
enableViewStateMac="true" validateRequest="false" />

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