EZproxy will not start up on Windows Server with the IIS role enabled. It produces errors that it is unable to bind to the login ports (typically 80 or 443) designated in the config.txt.
IIS Socket Pooling must be disabled to allow EZproxy to bind to the configured ports. See Microsoft support for information regarding disabling this feature.
Socket Pooling causes IIS to bind well known HTTP and HTTPS ports on every IP address.
Caution: OCLC does not recommend running EZproxy and Microsoft IIS on the same server, nor does it support such configurations.