A new Beta release for the Windows WARP client is now available on the beta releases downloads page.
This release contains minor fixes, improvements, and new features including Path Maximum Transmission Unit Discovery (PMTUD). With PMTUD enabled, the client will dynamically adjust packet sizing to optimize connection performance. There is also a new connection status message in the GUI to inform users that the local network connection may be unstable. This will make it easier to debug connectivity issues.
Changes and improvements
- Improvements for Windows multi-user to maintain the global WARP override state when switching between users.
- The GUI now displays the health of the tunnel and DNS connections by showing a connection status message when the network may be unstable. This will make it easier to debug connectivity issues.
- Deleting registrations no longer returns an error when succeeding.
- Path Maximum Transmission Unit Discovery (PMTUD) is now used to discover the effective MTU of the connection. This allows the client to improve connection performance optimized for the current network.
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 KB5062553 or higher for resolution.
Devices using WARP client 2025.4.929.0 and up may experience Local Domain Fallback failures if a fallback server has not been configured. To configure a fallback server, refer to Route traffic to fallback server.
Devices with KB5055523 installed may receive a warning about
Win32/ClickFix.ABAbeing present in the installer. To resolve this false positive, update Microsoft Security Intelligence to version 1.429.19.0 or later.DNS resolution may be broken when the following conditions are all true:
- WARP 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 WARP is connected.
To work around this issue, reconnect the WARP client by toggling off and back on.
Source: Cloudflare
