After you resume a Windows Vista-based DHCP client computer from sleep or from hibernation, the computer may lose its IP address. This problem may occur if there is more than one network interface on the computer, such as a real network interface and a virtual private network (VPN) interface.

For example, consider the following scenario:

• On a Windows Vista-based DHCP client computer, you establish a Secure Sockets Layer (SSL) VPN connection to a remote VPN server.
• You disconnect the SSL VPN connection.
• You put the computer to sleep or into hibernation.
• You resume the computer from sleep or from hibernation.

In this scenario, the computer loses the IP address that was assigned to it by the DHCP server. Instead, an Automatic Private IP Addressing (APIPA) address, such as 169.254.0.1, is assigned to the client computer. Therefore, you cannot access some network resources.