All times are Japan Standard Time (UTC+9).
Users of Killer and Intel connectivity software publicly report IPv6-only connection resets, often only to Microsoft services. They are told to check their ISP or reinstall Office, and are sent from one vendor to the next. See prior reports.
A post on Intel Community, from an HP ZBook owner, explains that the Intel connectivity service clears the IPv6 flow label at the TLS handshake and breaks cloud ECMP load balancing. Intel asks for details, then closes the inquiry for lack of a response, on 2025-09-22. The author re-posts in November, and Intel closes it again on 2025-11-12. In June 2026, organizations running HP EliteBooks add Microsoft 365 and SharePoint ERR_CONNECTION_RESET reports to the same thread. One notes that Windows Update reinstalled the software.
OneNote desktop shows notebooks as empty while reporting "Up to date". The pattern is documented: Microsoft endpoints reset over IPv6 and work over IPv4. It is reported through Microsoft Support article feedback, a public Feedback Portal idea and a Microsoft Support chat. The chat case is escalated for product review. The cause is not identified.
Windows' driver setup log on the affected laptop shows the Windows Update client installing ICPS packages: 4.1025.304.2 on 2025-05-07, then the 40.25.926.173 extension on 2026-05-10, the 40.25.926.173 component on 2026-05-14, and the extension again on 2026-06-13.
A user with Intel Wi-Fi 7 BE201 and ICPS 40.25.725.165 reports intermittent IPv6 failures against AWS CloudFront. Intel answers that it has no confirmed public advisory for the behavior. See prior reports.
OneNote's own logs show all three notebooks entering an error state ("We can't get to your notebooks right now"). They stay broken for nearly three weeks.
An OpenAI Codex session investigates the sync failure and abandons it without finding a cause.
Anthropic's Claude, running as an agent on the affected machine, takes over:
- It confirms that IPv6 connections to Microsoft's Azure Front Door edge are reset within one round trip, while IPv4 is clean.
- It captures traffic at the Wi-Fi miniport. Every post-handshake packet leaves with IPv6 Flow Label 0, and the RST comes from a different machine than the SYN-ACK (hop limit 49 vs 47).
- It inventories the Windows Filtering Platform callouts and isolates the AdGuard, AdGuard VPN, NetLimiter and Intel filter drivers one at a time.
With the Intel Connectivity Performance Suite driver (INTCCoSvc) and its services stopped, 10/10 IPv6 connections succeed and 65/65 packets keep their flow label. ICPS is left disabled: 10/10 connections, 73/73 labels. All three OneNote notebooks sync within seconds. Microsoft 365 sign-in works in Chromium browsers again.
- Microsoft: full root cause sent into the existing support case. Two public Feedback Hub reports filed (OneNote, Windows networking). Comment added to the Feedback Portal idea. Answer posted on Microsoft Q&A.
- Intel, 01:47: Intel Customer Support case opened and acknowledged.
- Intel, 02:08: Intel Community post published on the Wireless board.
- Samsung: Samsung Community US report posted, then hidden by Samsung's spam filter. Samsung Care support case opened through live chat, with escalation to Galaxy Book engineering requested.
- This public tracker is created.
Intel Customer Support says the OEM package may differ from Intel's generic releases, and asks for a clean removal followed by a test with the generic ICPS 50.26.623.243.
- 19:28–19:33: the original failure is reproduced on the OEM build. Re-enabling ICPS 40.25.926.173 drops IPv6 connections from 168/170 to 138/170 across 34 websites, with OneDrive, OneNote sync, Office, Teams, Skype, the Azure portal, Azure DevOps and the Visual Studio Marketplace resetting. Disabling it again restores 169/170.
- 20:58–21:07: the OEM packages are removed using the method in Intel's support article 000093451, the Store app and leftovers are removed with Revo Uninstaller, and the PC is restarted.
- 21:34: with no ICPS installed, 168/170 connections succeed and every packet keeps its flow label.
- 21:39: with Intel's generic ICPS 50.26.623.243 (driver 12.10.14.33) installed and its filters active, 169/170 succeed and all 11,711 post-handshake packets keep their flow label. See technical analysis.
- The results are sent to Intel. The Microsoft support case is asked to escalate beyond OneNote, after six weeks without an update.
- 01:03–02:05, Samsung US live chat: across four agents, Samsung says the October 3 case was "only for documentation", that it has no software engineering escalation department, and that the owner should contact Amazon or call a US phone line. A supervisor offers basic troubleshooting or a repair, neither of which can change a driver package delivered through Windows Update, then gives the address of Samsung Electronics America's Office of the President.
- A formal complaint and compensation claim is sent to the Office of the President, asking for the fixed package on Windows Update and a written reply within 14 days.
- An update is posted on the Samsung Community thread.
- Intel is sent the list of other affected laptop makers. See affected laptop makers.