When installing InterSystems IRIS on Windows, you may see the following option in the installer wizard if IIS has already been installed and enabled (Enable IIS).

Note: Depending on your installation type, you may not see this exact installer screen. In that case, proceed with installation as normal, and then configure the IIS settings on the server where the Web Gateway is installed.
If you choose to configure the local IIS web server for the instance, the installer wires IIS and the InterSystems Web Gateway together for you.

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