kb5086672 breaks network

KB5086672 is not a normal monthly update, it is an out of band optional update that Microsoft released to fix a bug logging into the Office apps caused by the March update.

If uninstalling that update resolves the problem, that is the best option, then pause your updates until the full April update is released next Tuesday.

I have the same issue too, rolled back the update & everything is back into action (mine's an Intel I225-v NIC). There're ways online to disable updates from auto updating, just search them up.

KB5086672 is not mentioned in the available context, so only general, context-backed guidance about network issues after updates can be provided.

When a Windows update breaks networking (for example with certain Realtek or other NIC drivers), the typical supported approaches are:

1. Roll back or avoid the problematic update
   • If uninstalling the update restores connectivity, keep it uninstalled and block its reinstallation until a fixed version is available.
   • On older Windows versions this is commonly done via Windows Server Update Services (WSUS) or by manually controlling which updates are installed, as described for other problematic networking updates such as KB4088875/KB4088878 and their prerequisite KB4099950.
2. Ensure any prerequisite or corrective updates are installed
   • For some networking issues, Microsoft ships a corrective update that must be installed before or along with the main cumulative update (for example, KB4099950 must be installed before KB4088875 or KB4088878 to avoid NIC/static IP issues on Windows 7/Server 2008 R2).
   • If Microsoft later publishes a servicing fix for KB5086672, install that fix first, then re-apply the cumulative update.
3. Update or correct the NIC driver
   • Similar to the documented Realtek issue after upgrading to Windows 8.1, networking can fail if Windows uses an in-box driver instead of the correct vendor driver. In that case, the resolution is to ensure the correct driver is applied rather than the generic one.
   • For a Realtek GBE Family Controller, install the latest Windows 11–compatible driver from the OEM or Realtek, then re-apply the update and test.
4. Use a hotfix or OS repair if Microsoft provides one
   • For other network-related issues (for example, WLAN chipsets or freezes when updating network drivers), Microsoft sometimes provides a targeted hotfix that must be installed on affected builds only.
   • If Microsoft publishes a specific hotfix or servicing stack update tied to KB5086672 networking failures, apply it on the affected system and then re-test networking.

If no specific fix for KB5086672 is available yet and uninstalling it is the only way to keep networking working, keep the update removed and prevent its reinstallation using the standard Windows update management tools (such as hiding the update or managing approvals via WSUS/endpoint management), and periodically check for a newer cumulative update that supersedes KB5086672 and resolves the issue.

References:

• NIC settings are replaced or static IP address settings are lost after you install KB4088875 or KB4088878
• No network connection after you upgrade to Windows 8.1 from Windows 8
• WLAN chipset no longer works after you install KB 2624668 in Windows 7 or in Windows Server 2008 R2
• Network adapter teaming breaks after you install the hotfix that is described in KB article 2487376 or 2495300 in Windows Vista SP2 or in Windows Server 2008 SP2
• Computer freezes when updating network driver or installing network filter driver in Windows 7 or Windows Server 2008 R2