Check line 42 in the AppXtender web.config is set to “False”. By default it is set to “False” Change value from false to true. Run a component registration wizard for Web Access and a reset IIS.
<!--
If request Full-Text License when Automatic Login with Windows Authentication.
true: Request for Full Text Search Support
false: Don't Request for Full Text Search Support.
-->
<add key="RequestFTLicForAutoLogin" value="false" />