A modified geoblock module originaly created by Triple IT for IIS 7/8.x. It can be added to any application pool using integrated pipeline mode running .Net 4 (now also on IIS 10). It uses the IPv4 address to determine the geographic location of the request by using Maxminds GeoIP2 database and takes action accordingly.
This may not work in all cases and has not been fully tested as I have no primary-IPv6 machines on hand or the time to spin them on VirtualBox. Having said that, once compiled it no longer produces errors in Event Log related to host address not matching a defined mask.
Please note it replaces first-party address matching with a library, which you may or may not be comfortable with. If you're fine with this approach I can submit a PR for a similar thing done to MaxMind libraries which have been released as nuget packages by MaxMind, obviating the need to have their .cs files in GeoIP.
This may not work in all cases and has not been fully tested as I have no primary-IPv6 machines on hand or the time to spin them on VirtualBox. Having said that, once compiled it no longer produces errors in Event Log related to host address not matching a defined mask.
Please note it replaces first-party address matching with a library, which you may or may not be comfortable with. If you're fine with this approach I can submit a PR for a similar thing done to MaxMind libraries which have been released as nuget packages by MaxMind, obviating the need to have their .cs files in GeoIP.