Das ist ein Missverständnis. "Domino Web Engine" heisst der Reiter.... Aber den hast Du ja gefunden
In der Admin Hilfe steht folgendes:
You can customize some of the error messages or responses that are generated by the Web server. If an "Error & Response" form-mapping document exists in DOMCFG.NSF, custom errors, not generic errors, are used.
To create a message page, create a form for each type of message and then create a mapping document in the Domino Configuration database (DOMCFG.NSF) to specify which form to display. While you can store message pages in any database, the one most commonly used is DOMCFG.NSF.
You can customize the messages that a user receives when:
The user fails to authenticate with the server.
The user is not authorized to access one of the databases that is part of the Web site on the server.
The user issues a command to delete a document from a database, and the server successfully completes the deletion.
The user's Internet password has expired.
The user attempts to change their Internet password and that is not allowed.
The user changes their Internet password and the change is submitted and accepted.
In addition, you can specify a general message that appears for all other types of errors or responses that occur on the Web server.
Note The general error message will not be generated for errors that occur when accessing non-database files. This type of custom error message only works when errors are encountered while accessing .NSF files.
If you enabled session-based name and password authentication, Domino displays an HTML page you specify to request name and password information from the user. Domino does not use customized error pages to display errors when authenticating with the server or accessing a database if session-based name and password authentication is enabled.Vielleicht ist das die Ursache. So ganz verstanden habe ich es aber beim ersten Lesen noch nicht....
Andreas