What does (Preferred), (Tentative) and (Duplicate) mean against an IPv4 Address with ipconfig

Solution 1:

Preferred is what your client will ask the DHCP server for when it gets/renews the lease, but tentative is what it got in the response. Someone else probably has a lease on the preferred address. Duplicate is what it says when windows detects an IP address conflict (and then probably switches to another address).

To manually release and renew now:

ipconfig /release
ipconfig /renew