I try to use Windows Server 2016 TP5 as BGP router.
There are 2 peers (Peer1&Peer2) advertising IPv4 default routes to us. Peer1 is controlled by me also. Both AS paths contains 2 AS.
If I make default route from some peer to have high priority (low weight or high localpref or short AS path) only this route appears in main route table (route print -4). When I stop this peer, Get-BgpRouteInformation shows low priority route as Best but this route doesn't appear in route table. When I start this peer again, no default route appears in route table at all!
Peer1 is Allied Telesys AT-770S. Peer2 is some Cisco router.
Windows Server 2012 R2 behavior is the same.