A malfunction in the network's DHCP server allows the same dynamic address to automatically be assigned to multiple computers.
The Internet Service Provider (ISP) accidentally assigns two customers the same IP address either statically or dynamically.
A mobile computer is put into a standby / hibernate mode and then awakened later.
Note that other forms of IP conflicts can also occur on a network. For example, one computer may experience an IP address conflict with itself if that computer is configured with multiple network adapters. System administrators may also create IP conflicts by accidentally connecting two ports of a network switch or router to each other.
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