Troubleshooting

I can’t connect to a server

Symptoms: the tile shows a red error, the status pill is Disconnected.

Step 1 — Is the host reachable?

Open a PowerShell window (Win+R, powershell, Enter) on your local machine:

Test-NetConnection <hostname-or-ip> -Port 3389

• TcpTestSucceeded: True — the network path is fine. Skip to step 2.
• TcpTestSucceeded: False — either the host isn’t running RDP on 3389, your firewall is blocking it, or DNS isn’t resolving. Check those before continuing.

Step 2 — Is RDP enabled on the target?

On the target machine:

1. Open Settings → System → Remote Desktop.
2. Enable Remote Desktop must be On.
3. The target’s Windows firewall must allow inbound RDP (Windows enables this rule automatically when you enable Remote Desktop, but corporate firewalls sometimes override).

Step 3 — Are the credentials correct?

If RDP is reachable and the error mentions credentials (A specified logon session does not exist, The password was incorrect, The account does not have permission), re-enter the credentials:

• In RDPMaster: right-click the profile → Edit → re-type username (with DOMAIN\username format if applicable) and password → Save → try connecting again.

Step 4 — Is NLA the problem?

Symptom: The remote computer requires Network Level Authentication.

NLA is a pre-authentication handshake. Some older Windows Server versions don’t speak NLA correctly, or the credentials must be entered in a specific format. Workaround: in the profile editor, uncheck Enable Network Level Authentication, save, retry. (Less secure but fast diagnostic.)

The session keeps dropping

Symptoms: status pill cycles Connected → Reconnecting → Connected every minute or so.

• Check Test-NetConnection over a longer period — packet loss often shows up as intermittent failures.
• If you’re on Wi-Fi, try Ethernet for a few minutes to compare.
• Some VPN clients (especially split-tunnel configs) interfere with RDP keep-alives. Disable VPN temporarily to isolate.
• RDPMaster has built-in auto-reconnect; the cycling is the recovery working, but the underlying connection is unstable. The root cause is almost always the network path between you and the host.

The remote desktop is blurry / pixelated after expand

The remote isn’t honoring the resolution-change request. Workaround: in the profile editor, turn Auto-resolution off and set a fixed Desktop Width + Desktop Height that matches your expanded view (e.g. 2560 × 1440).

This problem is much more common on Windows Server 2012 and earlier. Newer Windows versions handle dynamic resolution well.

Audio doesn’t work

In the profile editor:

• Audio = Play on client (the default) — audio plays on your local machine.
• Audio capture (microphone) requires Audio capture = Enabled AND that the target machine has microphone-in enabled in its Remote Desktop settings.

If audio still doesn’t work, the target may not have a sound device installed (common on headless servers). RDPMaster doesn’t synthesize one.

Clipboard doesn’t sync

Make sure Redirect clipboard is checked in the profile editor (it’s the default). If it’s on and clipboard still doesn’t move, the target’s RDP-Tcp policy may block clipboard redirection. Check the target’s Computer Configuration → Administrative Templates → Windows Components → Remote Desktop Services → Remote Desktop Session Host → Device and Resource Redirection group policies.

The app crashes on launch

Check %LOCALAPPDATA%\RDPMaster\logs\ for the most recent log file. The last few lines usually identify the failure. Common ones:

• Failed to resolve interface IID — missing or stale interop DLLs. Reinstall RDPMaster.
• COMException 0x80004005 — the bundled MsRdpClient ActiveX control failed to register. Run regsvr32 mstscax.dll in an elevated cmd, then relaunch.
• License blob signature invalid — your %APPDATA%\RDPMaster\license.dat is corrupted. Delete it; the trial will reissue on next launch.

Send the log to support@hudsonenterprisesllc.com for anything we don’t list here.

Where logs live

• %LOCALAPPDATA%\RDPMaster\logs\rdpmaster-YYYYMMDD.log — Serilog-formatted, one file per day, 14-day retention.
• Includes startup events, connection lifecycle, licensing decisions, errors.

When you email support, attach the most recent log file — it cuts diagnosis time roughly in half.

Reach a human

support@hudsonenterprisesllc.com — same business day. We don’t have a chatbot.