I previously used the POS environment and uninstalled it using the PSO installer. After that, I uninstalled the IIS and reinstalled the PSO. It installed without error. However, once I browsed the PSO event, I noticed a fatal error.

System.ServiceModel.AddressAlreadyInUseException: HTTP could not register URL http://+:8744/IFS/Scheduling/Gateway/Service/. Another application has already registered this URL with HTTP.SYS. ---> System.Net.HttpListenerException: Failed to listen on prefix 'http://+:8744/IFS/Scheduling/Gateway/Service/' because it conflicts with an existing registration on the machine. at System.Net.HttpListener.AddAllPrefixes() at System.Net.HttpListener.Start() at System.ServiceModel.Channels.SharedHttpTransp