Quick fix: Set explicit interface metrics to prioritize one adapter. Open Terminal (Admin) and run Set-NetIPInterface -InterfaceAlias "Ethernet" -InterfaceMetric 5 (low = preferred). Then Set-NetIPInterface -InterfaceAlias "Wi-Fi" -InterfaceMetric 50. Lower metric wins. Restart network adapter or PC.

Your laptop has both Ethernet and Wi-Fi connected. Some apps use Ethernet, some use Wi-Fi. VPN traffic confusingly splits. The cause: Windows auto-assigns adapter metrics; doesn’t reliably prefer one. Force explicit priority.

Symptom: Windows 11 sends traffic via multiple network adapters simultaneously; want one as primary.
Affects: Windows 11 (and Windows 10) with multiple active network adapters.
Fix time: ~10 minutes.

What causes this

Windows uses routing metrics to decide which adapter to send traffic. Each adapter has an Interface Metric; lower wins. Default metrics are auto-calculated based on link speed. Sometimes Wi-Fi 6 (potential 1+ Gbps) gets lower metric than Gigabit Ethernet, splitting traffic unpredictably. Manual metric assignment fixes.

Method 1: Set metrics via PowerShell (recommended)

The reliable route.

Open Terminal (Admin).

List current metrics:

Get-NetIPInterface -AddressFamily IPv4 | Format-Table InterfaceAlias, InterfaceMetric, ConnectionState

Set Ethernet to low metric (preferred):

Set-NetIPInterface -InterfaceAlias "Ethernet" -InterfaceMetric 5

Set Wi-Fi to higher metric:

Set-NetIPInterface -InterfaceAlias "Wi-Fi" -InterfaceMetric 50

For IPv6 separately:

Set-NetIPInterface -InterfaceAlias "Ethernet" -AddressFamily IPv6 -InterfaceMetric 5

Disable adapter you don’t want: Disable-NetAdapter -Name "Wi-Fi". Re-enable later: Enable-NetAdapter.
Test: visit a website. Verify it uses Ethernet by checking router’s connected devices.
To revert to automatic: Set-NetIPInterface -InterfaceAlias "Ethernet" -AutomaticMetric Enabled.

This is the standard metric setup.

Method 2: Configure GUI metric via ncpa.cpl

For GUI users.

Press Win + R, type ncpa.cpl, Enter.
Right-click Ethernet → Properties.
Double-click Internet Protocol Version 4 (TCP/IPv4).
Click Advanced.
Under Interface metric: untick Automatic metric. Enter low value: 5.
OK through all dialogs.
Repeat for Wi-Fi with metric 50.
Run ipconfig /release then ipconfig /renew.

This is the GUI equivalent.

Method 3: Disable specific binding to prevent traffic on adapter

For complete isolation.

For app-specific traffic on specific adapter: bind IP routing via route command.
For per-route preference:
```
route -p add 0.0.0.0 mask 0.0.0.0 192.168.1.1 metric 1 if 5
```
Where 192.168.1.1 = Ethernet gateway, if 5 = Ethernet interface index.
For IPv6 to use only Ethernet: Disable-NetAdapterBinding -Name "Wi-Fi" -ComponentID ms_tcpip6.
For VPN that should bypass Wi-Fi: configure VPN client’s split tunnel.
For permanent: change automatic adapter binding. PowerShell:
```
Set-NetAdapterBinding -Name "Wi-Fi" -ComponentID ms_tcpip -Enabled $false
```
Disables IPv4 on Wi-Fi entirely.

This is the right path for traffic isolation.

How to verify the fix worked

Run tracert google.com. First hop is Ethernet’s router IP.
Run Get-NetRoute -DestinationPrefix 0.0.0.0/0 | Format-Table InterfaceAlias, NextHop, RouteMetric. Default route shows Ethernet.
Open File Explorer → Network → verify connected via Ethernet.

If none of these work

If traffic still splits: Specific apps with adapter binding: some apps (BitTorrent, VPN clients) bind to specific adapter. Configure within app. For VPN tunneling: VPN may route through specific adapter. Check VPN client settings. For Wi-Fi as redundancy: Windows’s Multipath TCP may use both for performance. Set-NetTransportFilter can disable. For corporate-managed PCs: Group Policy may enforce specific routing. Check. For VPN drop-back to physical: when VPN drops, Windows reverts to physical adapter. Set kill switch in VPN client.

Bottom line: PowerShell Set-NetIPInterface -InterfaceMetric for each adapter. Lower wins. Ethernet 5, Wi-Fi 50 is a typical pair. Or disable unused adapter entirely.