I’ve been doing some work with a client recently implementing SmartConnect 2021, although the client has done much of the install themselves using the manual as a guide (this was their choice to help keep costs down). When we tried to enable the REST API and navigate to the endpoint to check, we were receiving an error:
HTTP Error 500.19 – Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid.
We did some investigation and research and found that the issue was that one of the required features had been missed during the installation. There are three elements of the WCF Services component of the .NET Framework 4.7 Features which need to be installed, but weren’t.
The screenshot below shows my demo system with the three components installed:
Once the client added these three components, the REST API worked correctly.