Clears and then populates the collection with DnsServer objects by looking up the following sources:

1. "MailBee.DnsMX.DnsServerCollection" key in the config file (and/or DnsServers if it's not empty).
2. Network interface.
3. Windows registry.
4. WMI database.

This overload will skip DNS servers with IPv6 addresses and won't add root 8.8.8.8 and 8.8.4.4 servers. See Autodetect(DnsAutodetectOptions) overload for more options.

Clears and then populates the collection with DnsServer objects by looking up the specified sources.