I have a rather strange problem with DHCP not working for a Belcarra USBLAN network adapter. I am testing a new driver (2.4.2.290 NDIS6) and it appears to offer DHCP to my host adapter, but my instance of Windows 7 64-bit ignores it. The older 2.3.8.7 driver uses NDIS5 and works fine. My wireshark log shows the driver providing an IP address, but it is apparently ignored. The system keeps requesting a new IP over and over again. I see four messages per transaction ID (discover, offer, request, ack). I've checked my policy and firewall settings. Nothing related to DHCP is configured for blocking. Belcarra is unable to reproduce my issue, and I've been able to confirm this is a configuration problem with my machine. A clean Windows 7 install does not exhibit this issue. Belcarra suspects a firewall configuration problem, which I don't fully understand because the 2.3 driver works on the same system. Any assistance with cleaning up my network stack on Windows 7 64-bit would be appreciated. Thanks! Additional software: Sophos Endpoint Security and Control 10.0Oracle VirtualBox 4.1.14Wireshark 1.4.4WinPCAP 4.1.2 Reference: * DHCP Broadcast Flag Post * Link to question on superuser.com Moved this from Microsoft Answers: http://answers.microsoft.com/en-us/windows/forum/windows_7-networking/windows-7-dhcp-ignored-link-local-usblan/d45a5f8c-e5c9-4589-a4ee-f50738034345 --Will

Turns out the problem was a configuration issue with the vendor's driver settings. A clean install did not have any errors. Upgrading from the 2.3.x driver to the 2.4.x driver left an entry that caused the problem. Remove this registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\ManufacturerName\UseClientIP

Hi, Glad to hear you worked out it. Hope your experience will help other community members facing similar problems :DTracy Cai TechNet Community Support