How to Fix WiFi Connectivity Issues Caused by MAC Address Randomization on Windows 11: When to Disable It and How It Affects DHCP Reservations and Router Filtering

Windows 11 ships with a privacy feature called Random Hardware Addresses that generates a new, randomized MAC address for your wireless adapter each time you connect to a network — or even each day on the same network. On public WiFi at airports, hotels, and coffee shops, this is exactly what you want: it makes your device harder to track as you move between locations. On your home network, however, randomized MACs break two common router features — DHCP reservations and MAC address filtering — in ways that cause persistent connectivity failures that are surprisingly difficult to diagnose. Run a speed test after following the fixes below to confirm your connection is stable and your router is assigning the correct IP.

How Windows 11 Random Hardware Addresses Works

Every network adapter has a burned-in hardware address called a MAC (Media Access Control) address — a 12-character hexadecimal identifier unique to your physical adapter. Your router uses this address to identify which device is which on your network. When Random Hardware Addresses is enabled, Windows substitutes a different, randomly generated address each time you associate with a network instead of presenting the real hardware address. Windows generates locally administered MAC addresses; you can identify them because the second hex digit is 2, 6, A, or E.

Windows 11 offers three randomization modes, configurable per saved network:

• Off: Windows uses your adapter’s real, permanent hardware MAC address. This is the correct setting for home networks where you use DHCP reservations or MAC filtering.
• On: Windows generates a fixed random MAC for this specific network and uses it consistently every time you connect to it. The same random address is used on each reconnect but differs from your hardware MAC.
• Change daily: Windows generates a new random MAC for this network every 24 hours. This mode is the most privacy-protective but breaks any feature that relies on a consistent MAC, including DHCP reservations and port forwarding rules.

Why Randomization Breaks DHCP Reservations

A DHCP reservation — called “address binding” or “manual assignment” on some routers — tells your router to always hand out the same IP address to a specific device, identified by its MAC address. This is how you give your NAS, printer, smart TV, or home server a predictable address for port forwarding or local DNS entries. When Windows presents a different MAC on every connection, the router does not recognize the device as the one with the reserved IP and assigns a random address from the DHCP pool instead. Your port forwarding rules, local DNS entries, and any application configured to reach that device at a specific IP silently break.

The symptom is usually indirect: your NAS becomes unreachable, your printer drops off the network, or a home automation hub stops communicating — not because those devices changed, but because your Windows laptop changed its MAC and received a different IP that no longer matches any reservation. The “Change daily” mode is especially disruptive because the failure recurs automatically every 24 hours with no user action to trigger it.

Why Randomization Breaks MAC Address Filtering

MAC address filtering is a router feature that maintains a whitelist of hardware addresses allowed to join the network. If your router is configured to only allow specific MACs, a Windows 11 device presenting a randomized address will be rejected every time it generates a new one — even if you previously added it to the whitelist. The device will fail association, appear to connect briefly before being dropped, or show up in the router’s device list with an unfamiliar address that does not match any whitelisted entry.

It is worth noting that MAC filtering provides limited security value on modern WiFi networks — MAC addresses are transmitted unencrypted and are trivially spoofable. If you are relying on MAC filtering for access control, consider switching to stronger mechanisms like WPA3-SAE or network segmentation. Our guide on IoT device network isolation covers VLAN-based segmentation as a more robust alternative.

How to Disable Random Hardware Addresses on Windows 11

Per-Network Setting (Recommended)

Disabling randomization per-network lets you keep it active on public WiFi while turning it off only for your home network. This is the recommended approach for most users.

1. Open Settings › Network & internet › WiFi.
2. Click Manage known networks.
3. Find your home network and click on it to expand its settings.
4. Locate the Random hardware addresses dropdown and change it to Off.
5. Disconnect and reconnect to your WiFi network so the router registers your permanent MAC immediately.

Global Setting

To disable randomization for all networks by default: go to Settings › Network & internet › WiFi, then find Random hardware addresses under the main WiFi toggles and set it to Off. Note that the global setting does not override per-network settings already configured explicitly — if a saved network has “Change daily” set at the network level, that will persist. Check each saved network individually if you continue seeing randomized MACs after changing the global toggle.

Finding Your Permanent MAC Address

Once randomization is disabled, you need your adapter’s actual hardware MAC address to create a correct DHCP reservation. Two easy methods:

• Command Prompt: Open a Command Prompt window and run getmac /v. The “Physical Address” column next to your WiFi adapter shows the permanent hardware MAC in XX-XX-XX-XX-XX-XX format.
• Settings: Go to Settings › Network & internet › WiFi › your network name › View Settings and scroll to “Physical (permanent) address.”

Log into your router’s admin page and add or update the DHCP reservation with this permanent address. On ASUS routers, navigate to LAN › DHCP Server › Manually Assigned IP. On TP-Link Archer routers, find it under Advanced › Network › DHCP Server › Address Reservation. On eero, reservations are set in the eero app under each device’s settings page. If you also maintain MAC filtering lists on your router, update those entries with the permanent address at the same time.

When to Keep Randomization Enabled

Random hardware addresses are most valuable on networks you do not fully trust — coffee shop WiFi, hotel networks, university networks, and retail guest networks. On these networks, randomization prevents venues from tracking your device across visits and blocks device fingerprinting by retail analytics systems. If you regularly connect your Windows 11 laptop to public hotspots, keep the per-network setting at On or Change daily for those networks while setting it to Off for your home SSID. The per-network control model in Windows 11 is specifically designed for this split — privacy protection on untrusted networks and stable identity on the home network where router features depend on a consistent MAC address. For further reading on how your router uses MAC addresses for security and filtering, see our guide on WPA2 vs WPA3 security.