topic Endpoint Security v89.10 - Network Connectivity Loss after Upgrade (Windows 10 & 11) in General Topics

Endpoint Security v89.10 - Network Connectivity Loss after Upgrade (Windows 10 & 11)

kiikoo15 — Mon, 06 Jul 2026 10:52:10 GMT

Hi everyone,

I am facing a issue after upgrading several client machines to Endpoint Security version 89.10.

After the update, multiple computers completely lost network connectivity (no internet, no local network access). This is affecting both Windows 10 and Windows 11 desktop machines.

A few details about our environment/behavior:

Impact: Both LAN (ethernet) and Wi-Fi seem to be affected/blocked.

OS: Windows 10 and Windows 11 (Desktops).

Has anyone experienced a similar issue with the 89.10 release? If so, did you find a specific workaround, or is there a known conflict with a recent Windows Update or specific network drivers?

Any insights or suggestions before I open an official TAC case would be greatly appreciated.

Thanks in advance!

Re: Endpoint Security v89.10 - Network Connectivity Loss after Upgrade (Windows 10 & 11)

MC142274 — Fri, 24 Jul 2026 14:09:51 GMT

YES! @kiikoo15 We faced the exact same thing several weeks ago as well. We initially saw correlation with our workstations that had installed a windows update around the same time so we paused the rollout. However a few days later we disproved that and instead saw correlation with our machines that had Realtek network controllers. Multiple times per day for some, once per day for others. The hardware network crashed so hard you couldn't even disable it from device manager. Only a reboot provided a temporary fix. So we tried a variety of different realtek drivers. We found some success in using the older win10 style driver instead of the windows 11 style since windows 11 can handle both types. However, eventually after several days they started having the same issue.

So the following week we switched a bunch of people over to PCIE Intel cards as a test. This seemed to have fixed things, however in the last 24 hours we had the issue on a wifi card that isn't realtek or intel. So we swung our attention over to AV after seeing your post, and sure enough, the reports did start to come in several days after that AV update. We are testing rollbacks today.

Re: Endpoint Security v89.10 - Network Connectivity Loss after Upgrade (Windows 10 & 11)

MC142274 — Mon, 03 Aug 2026 17:09:54 GMT

89.05 rollback seems to have fixed all issues.

We can confirm the issue is present in all versions 89.10 through 89.25