DirectDesk documentation

DirectDesk is a free remote desktop and remote support program for Windows. The same program shares your computer and connects you to others. Computers find each other by a 9-digit ID, with no accounts or passwords.

Requirements

• Windows 10 or Windows 11, 64-bit (x64).
• .NET 8 Desktop Runtime (x64) for the installer and winget. The portable Scoop version includes it.
• An internet connection: outbound TCP 443 to the signalling server and UDP (see Network and firewall).
• Administrator rights to install the full version.

Installation

Every method installs the same version, preconfigured for the Exatio server (57.129.182.38, port 443).

winget

DirectDesk is not in the public winget catalogue yet, so you add the Exatio source first. Run these commands in Terminal opened as administrator:

Skip the second command if .NET 8 Desktop Runtime is already installed. If it is missing, installing DirectDesk through winget ends with a missing dependency error.

The winget YAML manifests are also available as a ZIP archive. After unpacking you can install without adding the source: winget install --manifest .\Exatio.DirectDesk (run winget settings --enable LocalManifestFiles first).

Scoop

Scoop installs the portable version with .NET built in. It runs without the system service, so someone connected to this computer cannot send Ctrl+Alt+Del or see UAC prompts and the lock screen. Connecting to other computers works fully.

Installer

Download DirectDesk-Setup-1.0.1.exe (3.0 MB) and run it. The installer:

• copies the program to C:\Program Files\DirectDesk and adds a Start menu shortcut (and optionally a desktop shortcut),
• registers the DirectDesk service for Ctrl+Alt+Del and the secure desktop,
• adds a Windows Firewall rule for DirectDesk.exe,
• checks for .NET 8 Desktop Runtime and opens the Microsoft download page if it is missing.

Version 1.0.1 files are not digitally signed yet. If Windows SmartScreen shows a warning, click More info and Run anyway. Check the SHA-256 with Get-FileHash and compare it with SHA256SUMS.

First start

On first start the program generates this computer's ID: 9 digits in three groups, for example 258-343-583. The number is random, is not derived from the computer name and stays the same between starts.

• Twój identyfikator (your ID) is what you give to the person who should connect to your computer. Kopiuj (Copy) puts it on the clipboard.
• Nazwa tego komputera (this computer's name) is shown to your partner in the permission prompt. By default it is the Windows computer name.
• The status in the top right corner shows whether the program is connected to the server (online).

Connecting to a computer

1. Ask your partner to start DirectDesk and read out their ID.
2. Type the number in Połącz z komputerem (connect to a computer). You can paste it with dashes, spaces or the “DirectDesk-” prefix; the field tidies it up.
3. Optionally enter a name for this session, for example “Accounting”. The connection is saved under that name in recent sessions.
4. Click Połącz (Connect). Your partner sees a permission prompt with your computer's name.
5. Once accepted, the remote desktop window opens. A session panel appears in the bottom right corner of your partner's screen.

Double-click an entry in recent sessions to connect again.

Remote desktop window

The top bar shows the connection type (Bezpośrednio = direct, Przez serwer = via relay) and statistics: frames per second, throughput, picture resolution and response time.

• Control: click the picture to hand over mouse and keyboard. While the window has focus, keyboard shortcuts go to the partner's computer.
• Ctrl+Alt+Del: use the toolbar button. The program does not capture the key combination, because Windows always handles it locally.
• Lock screen and UAC: when your partner has the full installation with the service, you also see the secure desktop and administrator prompts.
• Rozłącz (Disconnect) ends the session. Closing the window does the same.

Files and clipboard

Files go both ways:

• from the remote desktop window: the Wyślij pliki and Wyślij folder buttons, or drag files onto the window,
• from the partner's computer: the same buttons in the session panel.

A folder is sent as a whole, with its subfolders, up to 5000 files at once. For several files the program asks for confirmation and shows their number and size. Received files go to Downloads\DirectDesk unless you choose another folder in the settings. Large files use a separate stream, so you can keep controlling the computer during a transfer.

The text clipboard is shared: text copied on one computer can be pasted on the other.

Settings

The Log tab shows the diagnostic log. Kopiuj log (copy log) is handy when reporting bugs.

Network and firewall

• Signalling server: outbound TCP to port 443. Only the session setup goes through the server.
• Direct connection: UDP between the computers. Works behind NAT routers too.
• Relay server (TURN): UDP port 3478. Used only when the direct path fails; the status then changes to Przez serwer.

The installer adds a Windows Firewall rule for DirectDesk.exe. The rule applies to this program only and opens no ports for other applications. The portable version adds no rule, so Windows may ask for permission on the first connection.

Security

• Every session has its own key agreed with ECDH on the P-256 curve. All traffic, including picture, input and files, is encrypted with AES-256-GCM.
• The signalling server only passes public keys and the information needed to set up the connection. It does not know the session key and never sees the picture. The relay server only forwards encrypted packets.
• The ID comes from a cryptographic random generator. By default every session needs approval and the session panel is visible the whole time.
• Limitation in version 1.0.1: the program does not show a key fingerprint for manual comparison, so it trusts the signalling server to pass the public keys. For full control, run your own server.

Your own server

The DirectDesk signalling server is a single static Go program that runs on any Linux. coturn acts as the relay server. The server code and a sample coturn configuration are in the source code archive.

Once your server is running, enter its IP address in Ustawienia → Adres serwera (Settings → server address) on every computer that should connect. Computers can only connect when they use the same server.

Troubleshooting

Status “offline” or no connection to the server

Check that the network allows outbound TCP to port 443 and that the settings contain the right server address.

“partner offline”

DirectDesk is not running on the partner's computer or is not connected to the server. Ask them to start the program and check its status.

“brak akceptacji” (not accepted)

Your partner did not accept the connection in time. Try again and ask them to click to allow it.

Slow picture with status “Przez serwer”

The direct connection failed and traffic goes through the relay server. Lower the resolution or the frame limit in the settings. Allowing UDP in a company network also helps.

Ctrl+Alt+Del does not work or UAC prompts are not visible

The partner's computer needs the full installation (winget or installer) with the DirectDesk service running. The portable Scoop version does not support this.

The program does not start

Install .NET 8 Desktop Runtime (x64): winget install --id Microsoft.DotNet.DesktopRuntime.8.

If the problem persists, report a bug and attach the log from Ustawienia → Log.

Updating and removing

Uninstalling removes the service and the firewall rule. The ID, settings and recent sessions are kept in %LocalAppData%\DirectDesk; that folder stays, so after reinstalling the computer keeps its number.