pascalposchenrieder

Hi,

thank you very much for the fast response and the fix. Do you already know when version 2026.2.2.0 will be released?

Best regards,

Pascal Poschenrieder

Confirmed regression (version bisect)

• ✅ Works: RDM 2025.3.9.2 (macOS, Jan 2026) — same Mac, same network, same connection entry, same gateway. Connects normally; the "Network transition / Pausing connections" log entries do not appear.

• ❌ Broken: RDM 2026.1.12.4 and 2026.2.1.2 — every connect fails instantly (0x00020008 / 0x00020006) due to the network-monitor loop described above.

• Last known-good was Jan 2026 on 2025.3.x; the regression is present in the 2026.1.x line and remains in 2026.2.x.

Conclusion: A change introduced between RDM 2025.3.9.2 and 2026.1.x added the RDP "network monitoring / network-transition pausing" behavior that breaks connections whose Host is only resolvable through the RD Gateway. Downgrading to 2025.3.9.2 is the current workaround.

Updated request: Please identify the change between 2025.3.9.2 and 2026.1.x that introduced this behavior, and provide a fix or a setting to disable the RDP network-monitoring/transition pausing — so we can run a current RDM version against gateway-brokered hosts.

Environment

• Remote Desktop Manager 2026.2.1.2 (64-bit), macOS (Apple Silicon)

• Embedded RDP engine: …/Remote Desktop Manager.app/Contents/MonoBundle/libDevolutionsRdp.dylib

• Connection type: RDP (Microsoft Remote Desktop) through an RD Gateway (WebSocket-based, open-source rdpgw)

• Gateway server: stage-rdpgw.oneclick.services:443 (valid Let's Encrypt cert, reachable, /remoteDesktopGateway/ returns HTTP 401 as expected)

• Connection Host: a per-session hostname (e.g. u3wsva2djj-stage.oneclick.services) that is only resolvable through the gateway, not via local/public DNS (by design — the gateway resolves it internally)

Problem Every connection attempt fails within ~3 seconds with:

ERROR Could not establish a secure connection to the host (0x00020008)

(occasionally Connection failed (0x00020006)). Nothing ever reaches the gateway server (verified server-side: no handshake/auth is logged).

Root cause (from RDM debug+verbose log) RemoteDesktopManager.debug shows, in the same second as the error:

DEBUG Network monitoring initialized for host: u3wsva2djj-stage.oneclick.services

DEBUG Network transition detected for host: u3wsva2djj-stage.oneclick.services - Pausing connections

DEBUG Certificate verification skipped: Network transition in progress

→ ERROR Could not establish a secure connection to the host (0x00020008)

The network monitor then loops endlessly, emitting dozens of identical lines per second and never settling:

DEBUG Network restored for host: … - Starting stabilization period

DEBUG Network transition detected for host: … - Pausing connections

It appears the network monitor performs a reachability check tied to the connection's Host, and because that Host is only resolvable via the gateway (not local DNS), the check fails permanently → it perpetually reports a "network transition" and pauses the connection, so the actual connect never proceeds (TLS/cert verification is explicitly skipped).

Proof this is RDM-specific (not network/gateway/target)

• The native Microsoft RDP client (Windows App / mstsc) connects successfully to the same gateway + same Host from the same Mac and network.

• A FreeRDP 3.x-based client also connects successfully to the same gateway.

• Gateway endpoint reachable from the Mac (TCP/TLS OK via openssl/nc); macOS Application Firewall is disabled; no Little Snitch / network-filter extensions.

• This connection worked previously (January 2026) on an older RDM version (which used the separate FreeRDPSandboxed.app engine and did not have this network-monitoring behavior). On 2026.2.x no SessionLogs/*.log is written for these attempts — the engine aborts before a session starts.

Already tried (no effect)

• Clean reinstall of RDM 2026.2.1.2

• Recreating the connection entry from scratch

• Gateway Transport = Auto and = HTTP

• Stopping Tailscale/VPN (the monitor kept flapping for 90s+ afterwards)

• No user-facing toggle for this in RemoteDesktopManager.cfg

Questions / request

1. How can the RDP network-monitoring / "network transition" pausing behavior be disabled?

2. This looks like a false-positive when the RDP Host is only resolvable through the RD Gateway (common with gateway-brokered/per-session hostnames). Can the monitor be fixed to not block such connections (e.g. check the gateway reachability instead of the inner Host)?

environment:

• MACOS: Sequoia 15.3.2

• RDM Mac: 2025.1.16.1

fail to RDP via RD Gateway with the following error.

if making RDP connection directly (without using RD gateway), no error.

The same RDP entry was working in previous version 2024.3.5.1. I got this error right after upgrade to version 2025.1.16.1

I have the exact same issue on MacOS Sequoia 15.3.1 since RDM version 2025.1.16.1.

I downgraded to RDM 2025.1.13.3 and there it is working like expected.

In the RemoteDesktopManager.log I get the following error:

[05.05.2025 12:40:07]INFO Remaining reconnection attempts: 4

[05.05.2025 12:40:08 - 2025.1.16.1 64-bit]ERROR NSInvalidReceivePortException: connection went invalid while waiting for a reply

Sometimes I get a little bit different error message:

[05.05.2025 12:29:30]INFO Remaining reconnection attempts: 4

[05.05.2025 12:29:31 - 2025.1.16.1 64-bit]ERROR NSInvalidReceivePortException: connection went invalid while waiting for a reply because a mach port died

As we recommend Remote Desktop Manager to all our customers it would be great if this issue could be fixed as fast as possible. All our Mac customers are using a RD Gateway and we get a lot off error reports right now.

Thanks for the input to downgrade! I have troubleshoot for three hours why the heck it didnt work until I tested to use "Windows App" with the gateway and that worked.

You can also get the RDM Version 2025.1.13.3 here: https://devolutions.net/remote-desktop-manager/home/previousversions/

environment:

• MACOS: Sequoia 15.3.2

• RDM Mac: 2025.1.16.1

fail to RDP via RD Gateway with the following error.

if making RDP connection directly (without using RD gateway), no error.

The same RDP entry was working in previous version 2024.3.5.1. I got this error right after upgrade to version 2025.1.16.1

I have the exact same issue on MacOS Sequoia 15.3.1 since RDM version 2025.1.16.1.

I downgraded to RDM 2025.1.13.3 and there it is working like expected.

In the RemoteDesktopManager.log I get the following error:

[05.05.2025 12:40:07]INFO Remaining reconnection attempts: 4
[05.05.2025 12:40:08 - 2025.1.16.1 64-bit]ERROR NSInvalidReceivePortException: connection went invalid while waiting for a reply

Sometimes I get a little bit different error message:

[05.05.2025 12:29:30]INFO Remaining reconnection attempts: 4
[05.05.2025 12:29:31 - 2025.1.16.1 64-bit]ERROR NSInvalidReceivePortException: connection went invalid while waiting for a reply because a mach port died

As we recommend Remote Desktop Manager to all our customers it would be great if this issue could be fixed as fast as possible. All our Mac customers are using a RD Gateway and we get a lot off error reports right now.