Help & FAQ for Linux
The help that comes with Alcedo RDP for Linux, so you can read it before you install. In the app it is under the ? button in the sidebar.
Using Mac? Read the Mac help & FAQ.
Getting Started
Alcedo RDP connects your Linux desktop to Windows PCs and servers over Remote Desktop (RDP), and to Azure Virtual Desktop, Windows 365 Cloud PCs and on-premises Remote Desktop Services feeds.
How it works
Each remote computer you use is saved as a connection. Connections appear as cards in the main window, can be grouped and marked as favorites, and remember every setting for that computer — resolution, which local devices to share, and performance options. When you connect, the remote desktop opens in its own window.
Add a connection
- Click Add Connection in the toolbar.
- On the General tab enter a display name and the computer's host name or IP address. The default RDP port is 3389.
- Optionally enter the username, domain and password. Passwords are stored in your desktop's keyring (GNOME Keyring or KDE Wallet via the Secret Service), never in plain text.
- Review the Display, Resources, Experience and Gateway tabs — see Connection Settings — then click Save.
Connect
Double-click a connection card, or click its ▶ button. If no password is saved you are asked to sign in; the credentials you enter are saved to the keyring and to the connection so you aren't asked again. The first time you reach a server whose certificate isn't trusted, Alcedo shows the certificate details and lets you Reject it, Accept once, or Always trust it.
Import and workspaces
Organize
Connection Settings
Every option in the New / Edit Connection dialog (the pencil on a card). Settings are stored per connection.
General
Display
Resources
Which local devices the remote session can use. Everything here is off by default except the clipboard; turn on only what you need.
Experience
The modern graphics pipeline and RemoteFX codecs are always negotiated automatically; there is nothing to configure.
Gateway
In a Session
Every connection opens in its own window; you can keep several sessions open side by side.
The session toolbar
Move the pointer to the very top edge of the session window and a toolbar slides in. It hides again when the pointer leaves it.
Resizing and scaling
With Match window size (the default), resizing the window asks the remote computer to change its desktop size to match, so the picture stays pixel-for-pixel. With a Custom size the picture is shown at its true size and letterboxed. The remote UI scale (100 %, 150 % …) follows your local display scaling.
Clipboard
Text and images are synchronized both ways while Clipboard is enabled for the connection. File copy and paste is not supported.
RemoteApp sessions
For RemoteApp connections the session window only shows a status panel; each window the remote program opens appears as its own window on your desktop and can be moved, resized and closed like a local one. End session closes the program and disconnects.
When the connection drops
If the network drops, Alcedo tries to reconnect automatically for a short while and shows Reconnecting over the frozen session. A successful reconnect brings your programs and windows back exactly as they were.
If it can't get back in, or the server disconnected you on purpose — you were signed out, another device took the session over, or the connection failed — the window shows Disconnected or Connection failed with the reason, and offers Reconnect and Close.
Cloud & Workspaces
Azure Virtual Desktop, Windows 365 Cloud PCs and on-premises Remote Desktop Services feeds show up next to your own connections.
Sign in with a work or school account
- Open Azure & Cloud PCs in the sidebar and click Sign In (also available in Settings).
- Your browser opens the Microsoft sign-in page. Sign in with your Microsoft Entra ID account; Alcedo asks for permission to read your Cloud PCs and Virtual Desktop resources.
- Back in Alcedo, your workspaces and Cloud PCs are listed. Click Refresh any time to fetch the latest list.
Tip The first time you open a Virtual Desktop resource, Microsoft requires a second device-code sign-in. Alcedo copies the code to the clipboard and opens the verification page — paste the code there and the dialog closes by itself.
Workspaces and Cloud PCs
On-premises Remote Desktop Services
Use ⋯ › Add workspace feed… with the RD Web Access feed URL from your own Remote Desktop Services deployment, plus your domain username and password. The published desktops and apps are imported as regular connections that you can edit, group and favorite like any other.
Print, Scan & Webcam
The TerminalWorks add-ons bring local printers, scanners and cameras into the remote session. Turn each one on per connection (Resources tab, or Session Settings on a cloud card). Each needs its server component installed on the remote computer.
TSPrint — printing
Requires TSPrint Server on the remote computer. Printing to the TSPrint printer in the session opens Alcedo's Print dialog on your desktop with a page preview, and prints through CUPS to any printer configured on this computer.
TSScan — scanning
Requires TSScan Server on the remote computer. Scanners are found through SANE, so anything that works in your desktop's scanning app works here. When a remote application asks to scan, Alcedo's Scan dialog opens.
TSWebCam — camera
Requires TSWebCam Server on the remote computer. Your camera (any Video4Linux device) is encoded as H.264 and appears as a webcam inside the remote session for video calls and capture applications.
Note Scanners and cameras need device access: make sure your user can open the device (typically membership of the scanner and video groups, or the udev rules your distribution installs with SANE).
App Settings
The gear button at the bottom of the sidebar. Three tabs; every change applies immediately.
General
Cloud
About
The app version and build number — include them when reporting an issue — and links to Help, the website and support.
Where things are stored
Keyboard & Mouse
Inside a session every key you press goes to the remote computer, including modifiers and the Super (Windows) key where your desktop environment lets it through.
In a session
- Ctrl+Alt+End
- Send Ctrl+Alt+Del to the remote computer (the local OS reserves Ctrl+Alt+Del)
- F11
- Toggle full screen (Ctrl+Alt+Enter does the same)
- Top edge hover
- Reveal the session toolbar (Ctrl+Alt+Del, Windows key, Fullscreen, Disconnect)
- Mouse wheel
- Vertical and horizontal scrolling are forwarded, including touchpad two-finger scrolling
- Pinch
- Touchpad pinch zooms the remote program (sent as Ctrl + mouse wheel). Needs a desktop that reports pinch gestures — Wayland does, X11 doesn't.
- Right / middle click
- Forwarded as on Windows
Main window
- F1
- Open this help
- Double-click a card
- Connect
Print and Scan dialogs
- Enter
- Esc
- Cancel the dialog
Tip Some desktop environments grab shortcuts such as Super, Alt+Tab or Alt+F4 before Alcedo sees them. Use the session in full screen, or change the shortcut in your desktop's keyboard settings, if you need those keys on the remote side.
Troubleshooting
"Connection failed"
The disconnected screen shows the reason reported by the remote computer or by the network layer. Common causes:
"We couldn't establish a secure connection" (TLS)
The remote PC accepted the connection but the TLS handshake failed (error code 0x0008). The common cause on the Linux client is a server, or a TLS-inspecting firewall in front of it, that rejects a handshake offering only modern signatures — the client's OpenSSL no longer advertises the old SHA-1 one that Windows still does.
On the failed screen, click Retry with legacy TLS to reconnect once with that signature re-enabled. To make it permanent for that connection, turn on Legacy TLS compatibility on its Gateway tab. It is a small security downgrade, so use it only where a connection needs it; the real fix is a certificate or TLS update on the server.
Certificate warning
On the first connection to a server with a self-signed or otherwise untrusted certificate, Alcedo shows its details. Accept once trusts it for this session only; Always trust remembers it. If the certificate of a known server suddenly changes, be cautious — verify with your administrator before accepting.
Another device connected to this session
Windows allows one active connection per user session. When you (or a colleague using the same account) connect from another computer, that computer takes the session over and this one is disconnected. Reconnect from the computer you want to use and the session moves back.
Passwords aren't remembered
Alcedo stores passwords in the desktop keyring. If no Secret Service is available — a minimal window manager without GNOME Keyring or KDE Wallet, or a locked keyring — saving fails silently and you are asked for the password each time. Start or unlock your keyring, or install gnome-keyring.
Sign-in to on-premises servers always fails
NTLM sign-in (workgroup PCs, RD Web feeds) needs the OpenSSL legacy provider for MD4/RC4. The AppImage bundles it; if you built Alcedo yourself and the terminal shows "OpenSSL legacy provider unavailable", install your distribution's OpenSSL legacy provider package.
Display server notes
The AppImage runs on X11 (XWayland on Wayland desktops) by default because that is the most dependable choice for a bundled Qt. To try native Wayland, start it with QT_QPA_PLATFORM=wayland.
Printing problems (TSPrint)
TSPrint Server sends each print job to Alcedo, which shows the Print dialog and hands the document to CUPS. If a job never arrives, the dialog shows the wrong paper or tray, or nothing comes out of the printer, the client-side log shows each step.
Scanning problems (TSScan)
Alcedo lists the scanners SANE knows about (what scanimage -L shows) and sends the list to TSScan Server when the remote application asks. If the remote side shows no scanners or its application closes while loading devices, the client-side log tells us what was found and exactly what was sent.
Webcam problems (TSWebCam)
Alcedo lists the cameras it can capture from (V4L2 devices with a raw format) and streams H.264 to TSWebCam Server, which shows them as a virtual camera in the session. If no camera is listed or the picture never starts, the client-side log shows the cameras found and the capture pipeline.
Collecting logs
Every launch writes alcedo-app.log and alcedo-freerdp.log to /tmp (or $TMPDIR) for the session itself; they are recreated on each launch.
The add-on logs — tsprint_debug.log, tsscan_debug.log and tswebcam_debug.log — are written only on request: turn on Developer mode in Settings › General (or start Alcedo with --dev), switch the add-on on in the connection's Logging tab (Edit dialog, or Session Settings on a cloud card), then connect and reproduce the problem. They are appended across launches with a banner per run and trimmed once they pass 2 MB. Attach the files to a Report an Issue email — together with the Windows Event Viewer entry when the remote application crashed.
Still stuck?
Visit the TerminalWorks support site, or use Report an Issue to email [email protected]. Please include the message shown on the disconnected screen, the Windows version of the remote computer and your Linux distribution — the email template fills in the app version for you. The log files in /tmp (see Collecting logs above) help with anything that can't be seen on screen.