User-460007017 posted
Hi Torviael,
To disable the client impersonation, please go to IIS manager->server/site level->authentications->asp.net impersonation->disable. In addition, you could try to add validation attribute in system.webserver.
<configuration>
<system.webServer>
<validation validateIntegratedModeConfiguration="true" />
</system.webServer>
</configuration>
If the steps is not working, please compare the config file with the correct one.
Best Regards,
Yuk Ding