I have been recently asked a question (by the way through new Jabber/XMPP/GoogleTalk based web chat) about DHCP Server leases.
I’m using the trial version of Alax.Info DHCP Server
And it says there are no more IP addresses available… Do I have to register?
Registration definitely would not hurt, however there is also an alternative. Issued leases are kept in registry under HKEY_LOCAL_MACHINE\SOFTWARE\Alax.Info\DhcpServer\Leases key. It is possible to open registry editor and remove some of the leases or even delete all of them (or rename key to be able to restore) in order to reset current DHCP Server state and allow it issue new leases again. This trick resets lease counter and allows having new five IP addresses given out by server to old or new MAC addresses.