Cannot add duplicate collection entry of type 'add' with unique key attribute 'name' set to 'X-FRAME-OPTIONS'
Cannot add duplicate collection entry of type 'add' with unique key attribute 'name' set to 'X-Content-Type-Options'
These errors are caused by Custom Headers being set in the web.config and set at the server level in IIS. The following settings: Content-Security-Policy, X-Content-Type-Options, and, X-FRAME-OPTIONS cannot be set in both places.
To correct the issue, you can remove the settings at the server level.
Launch IIS Manager.
Select the server in the left panel.
Double-click on HTTP Response Headers in the middle panel as shown here:
4. You can then select the setting then click remove on the right pane.
The following settings were added to the web.config in Archer 6.9
The recommended settings are set in the web.config but before making the above changes please refer to the Security Configuration Guide for more information about the above settings and to your companies policies to ensure that removing these settings does not violate any of your policies.