1
Diagnostic step 1
Capture network traffic on the laptop while reproducing the issue using Wireshark: filter for bootp or udp port 67/68 to see whether DHCPDISCOVER is transmitted and whether DHCPOFFER arrives. This is reversible and read-only.
FULL AI ANALYSIS
Windows 11: Wi‑Fi connects to SSID but obtains APIPA (169.254.x.x) until adapter restart
Generated Oct 3, 2026, 12:35:03 AM
Analysis summary
Symptoms point at a DHCP client handshake failing specifically over the Wi‑Fi interface in certain connection sequences (resumes, switching hotspots). Observations (DHCP client warnings in System log, no entry in router lease table) indicate the DHCPDISCOVER/DHCPREQUEST exchange never completes or the packets are dropped locally. The fact that adapter disable/re-enable or ipconfig /renew fixes it suggests a local state issue (driver, offload/power features, or filtering by third-party networking software) rather than router DHCP server being universally broken.
Possible causes
Bug or race in the Wi‑Fi driver causing DHCP client to fail to send or receive DHCP packets until adapter reset (driver state machine or offload features).
85%Power-management features (ARP offload, packet coalescing, WoWLAN) interfering with broadcast DHCP on resume, causing DHCPDISCOVER to be dropped or transmitted on wrong VLAN.
75%IPv4 DHCP client service timing issue: service not bound to Wi‑Fi adapter quickly enough on resume leading to missed replies with the DHCP server not responding to late requests.
55%Local Windows firewall or third-party security/antivirus network filtering blocking DHCP traffic when reconnection occurs after specific sequences (host remains in a transitional profile).
15%Suggested fixes
2
Diagnostic step 2
Temporarily disable third-party security/network filtering (antivirus firewall) and retest to rule out packet filtering interference. If disabled, re-enable after test.
3
Diagnostic step 3
Set Wi‑Fi adapter advanced properties: disable 'Allow computer to turn off this device to save power', disable 'Wake on Magic Packet' and 'ARP offload' options; test after each change to isolate guilty feature. These changes are reversible from Device Manager.
4
Diagnostic step 4
If driver update was from OEM, try installing the vendor-provided driver (Intel generic vs Dell OEM) and/or roll back to a known-good driver; keep a copy of current driver to restore if necessary.
5
Diagnostic step 5
If Wireshark shows DHCPDISCOVER sent but no DHCPOFFER received, test with a different router/access point or a temporary open hotspot to see whether server replies are blocked. If DHCPOFFER arrives but not processed, inspect Windows DHCP Client service: restart it and review service dependencies; check Event Viewer for DHCP client errors in detail and collect logs for escalation to Microsoft or NIC vendor support if driver-level debugging is needed.