An item with the same key has already been added

The reason for this error received in Bimserviewer is:

It is broadcasting with Http and Https under a single Default Web Site on the server.

For this reason, this error is received in the system when trying to reach Bimserviewere from IIS.

Note: The link above the image is the Bimserviewer link, the link of the portal remained while the screenshot was taken. Don't let it fool you.