Cloudflare One Client for Windows 2026.3.851.0

A new GA release for the Windows Cloudflare One Client is now available on the stable releases downloads page.

This release contains minor fixes and improvements.

The next stable release for Windows will introduce the new Cloudflare One Client UI, providing a cleaner and more intuitive design as well as easier access to common actions and information.

Changes and improvements

• Fixed an issue causing Windows client tunnel interface initialization failure which prevented clients from establishing a tunnel for connection.
• Consumer-only CLI commands are now clearly distinguished from Zero Trust commands.
• Added detailed QUIC connection metrics to diagnostic logs for better troubleshooting.
• Added monitoring for tunnel statistics collection timeouts.
• Switched tunnel congestion control algorithm for local proxy mode to Cubic for improved reliability across platforms.
• Fixed packet capture failing on tunnel interface when the tunnel interface is renamed by SCCM VPN boundary support.
• Fixed unnecessary registration deletion caused by RDP connections in multi-user mode.
• Fixed increased tunnel interface start-up time due to a race between duplicate address detection (DAD) and disabling NetBT.
• Fixed tunnel failing to connect when the system DNS search list contains unexpected characters.
• Empty MDM files are now rejected instead of being incorrectly accepted as a single MDM config.
• Fixed an issue in local proxy mode where the client could become unresponsive due to upstream connection timeouts.
• Fixed an issue where the emergency disconnect status of a prior organization persisted after a switch to a different organization.
• Fixed initiating managed network detections checks when no network is available, which caused device profile flapping.
• Fixed an issue where degraded Windows Management Instrumentation (WMI) state could put the client in a failed connection state loop during initialization.

Known issues

• For Windows 11 24H2 users, Microsoft has confirmed a regression that may lead to performance issues like mouse lag, audio cracking, or other slowdowns. Cloudflare recommends users experiencing these issues upgrade to a minimum Windows 11 24H2 version KB5062553 or higher for resolution. This warning will be omitted from future release notes. This Windows update was released in July 2025.

• Devices with KB5055523 installed may receive a warning about Win32/ClickFix.ABA being present in the installer. To resolve this false positive, update Microsoft Security Intelligence to version 1.429.19.0 or later. This warning will be omitted from future release notes. This Microsoft Security Intelligence update was released in May 2025.

• DNS resolution may be broken when the following conditions are all true:

  • The client is in Secure Web Gateway without DNS filtering (tunnel-only) mode.
  • A custom DNS server address is configured on the primary network adapter.
  • The custom DNS server address on the primary network adapter is changed while the client is connected.

  To work around this issue, reconnect the client by selecting Disconnect and then Connect in the client user interface.