Calls & Conferences Troubleshooting

Microphone or camera access errors

Is the Antivirus Blocking Devices?

Check if your antivirus or firewall is blocking access to the microphone and camera (in the desktop version). Contact your organization’s support for assistance.

For Advanced Users: Adding the app to Kaspersky Antivirus Exclusions (Windows)

• 1. If the app is installed in the current user’s folder, the path is:
  %LOCALAPPDATA%\Programs\eXpress\eXpress.exe If the app is installed in the Program Files folder, the path is:
  %PROGRAMFILES%\eXpress\eXpress.exe
• 2. Open Settings > Threats & Exclusions.
• 3. Then select Configure Exclusions. Specify the app path, select All components, and click Add.
• 4. Select Specify Trusted Applications. Specify the app path, check the boxes Do not scan opened files, Do not monitor app activity, Do not inherit parent process restrictions, select Status > Active, and click OK.
• 5. After adding the app to exclusions, restart your computer.

Are Other Applications Using the Camera or Microphone?

Some third-party apps may retain access to the microphone and camera even after ending a call. Terminate their processes or restart your computer.

Are Devices Not Connected or Not Forwarded?

Open Settings (avatar above the chat list) > Calls or Call settings and check the selected devices in the Microphone and Camera fields. If the fields are empty, there is no access to the devices:

• Ensure the devices are connected.
• When using RDP or VDI, check the settings. Contact support for assistance.

If the issue persists, try using the web app in a browser.

No Access to Devices in the Browser or OS?

For the web app, check browser permissions:

How to check browser permissions for microphone and camera access

Browser	How to grant access
Apple Safari	Menu Safari > Preferences > Websites > app address > Microphone/Camera > Allow
Chromium, Google Chrome	Settings > Privacy & Security > Site Settings > Microphone/Camera
Microsoft Edge	Settings > Cookies & Site Permissions > Microphone/Camera
Mozilla Firefox	Settings > Privacy & Security > Permissions > Microphone/Camera
Opera, Vivaldi	Settings > Privacy > Microphone/Camera
Yandex Browser	Settings > Sites > Advanced Site Settings > Microphone Access/Camera

For the desktop version, check OS permissions:

How to check operating system permissions

OS	How to grant access
macOS	Apple menu > System Preferences > Security & Privacy > Privacy > Microphone/Camera > check the box next to the app, then restart it.
Linux	Refer to your OS documentation
Windows	Settings > Privacy > Microphone/Camera > enable Allow desktop apps to access

Are Devices Not Working?

Check the functionality of the microphone and camera. Before testing, ensure these test websites are allowed to access the devices (see step 4).

Microphone: online-voice-recorder.com:

1. Click the record button.
2. Grant permission to use the microphone.
3. Stop the recording and listen to the result. If the microphone is not detected or there is no recording, check the connection and drivers.

Camera: webcamtests.com:

1. Select the camera from the list (if multiple are available).
2. Click Test my cam.
3. If the camera does not work, check its physical connection and settings.

Sound, Video, and Echo Issues in Calls

A Pulsing Repeating Sound Is Heard During a Call

This is the standard call connection sound, not a headset or line malfunction. It stops as soon as the connection is established.

Is a Legacy App Version Being Used?

Use the latest version of the app with the most recent fixes and improvements for calls and conferences.

Are There Network Connection Issues?

• If you experience freezes, loss of video or audio, or “robot voice,” ensure your network connection meets these requirements.
• Avoid using VPN if possible.
• Try connecting to a different network.
• You can also reduce video and audio quality in the call settings.
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  If necessary, the server administrator can centrally configure audio and video quality in the admin panel.

Is There a Source of Constant Noise?

If there is background noise on your end, try enabling noise suppression in the call settings.

Is There External Echo?

If you hear an echo of your own voice, the issue is likely on the other party's side. Ask them to reduce speaker/microphone volume or use headphones. For persistent echo issues, also consider checking acoustic echo cancellation settings in your device's audio properties.

Is a Low-Performance Computer Being Used?

If your computer has low performance, enable CPU resource saving in the call settings in the Web/Desktop app and close other unnecessary applications.

Nothing Helped?

If the issue persists, perform the following checks:

• Try joining the call from another device (e.g., a smartphone).
• Ask other participants if they are experiencing the same issue.

This will help identify the source of the problem:

• If everyone has the issue — it is widespread; contact support.
• If the issue is only on your device — check its settings using the recommendations above.

If you cannot resolve the issue yourself, contact your organization's support or eXpress support.

No Remote Control Button, Cannot Share Other Windows Except eXpress (Desktop, Windows)

Contact your system administrator, your organization's support, or eXpress support to resolve the issue.

For Administrators: Check Windows Application Restrictions

In the log.log file from the desktop application folder, you may find a line like Error: This program is blocked by group policy ... \AppData\Local\Temp\XXX.tmp.node. This means that the execution of temporary Electron files (the desktop app engine) is blocked. To verify this, run the following commands on the affected computer:

• gpresult /h C:\Temp\gpo_report.html — summary of applied policies. See the AppLocker, Software Restriction Policies, Windows Components → Privacy sections.
• Get-AppLockerPolicy -Effective | Select-Object -ExpandProperty RuleCollections — active AppLocker policies. Look for a rule that blocks execution from the %TEMP% (%LOCALAPPDATA%\Temp) folder.
• Windows Settings > Privacy & Security > Screenshots and Screen Recording > Allow classic apps to take screenshots — should be set to ON.
• Try temporarily disabling your antivirus if the restrictions above are not present.

If you find that any restriction is active, disable it or add exceptions for running %LOCALAPPDATA%\Temp\*.node (%TEMP%\*.node) files.

Call or Conference Participants Cannot Hear Me

Call participants cannot hear you and the microphone indicator is inactive.

Are the Devices Functional and Selected?

Ensure the microphone or headset is turned on, functioning correctly, and selected in call settings.

Check that the correct microphone is selected in the system and disable unnecessary devices:

Operating System	Steps
Windows 10/11	Open Settings > System > Sound. Under Input, select the microphone. Click Manage sound devices and disable unnecessary devices.
Windows 7/8	Open Control Panel > Hardware and Sound > Sound > Recording. Right-click the microphone and select Set as Default Device. Disable unnecessary devices via the context menu.
macOS	Open Apple > System Preferences > Sound > Input. Select the desired microphone.
Linux (Ubuntu 20+)	Open Settings > Sound. Under Input, select the microphone.

Is the Microphone Volume Set Correctly?

Operating System	Steps
Windows 10/11	Open Settings > System > Sound. Under Input, select the microphone and click Device properties. Adjust the Volume slider.
Windows 7/8	Open Control Panel > Hardware and Sound > Sound > Recording. Double-click the microphone and adjust the Microphone value under the Levels tab.
macOS	Open Apple > System Preferences > Sound > Input. Select the microphone and adjust the Volume.
Linux (Ubuntu 20+)	Open Settings > Sound. Under Input, select the microphone and adjust the Volume.

Is Network Connectivity Restricted?

Check the network access requirements. Contact your organization support if necessary.

Nothing Helped?

If the issue persists, contact your organization support or eXpress support.

The eXpress Desktop App Does not Use the Default Input/Output Device

To make the app use the system's default audio output device (Windows/macOS), select the device labeled Default in call settings.

For the microphone:

• In Windows, select the device labeled Communications.
• In macOS, select the device labeled Default.

Calls Don't Work in the Web App, but Chats Do

Messaging and files work in the web app, but a call doesn't connect, or there is no audio or video. At the same time, calls work in the desktop app on the same computer.

Are You Working Over VPN?

Check whether the problem persists with VPN disabled. If calls work without VPN, the issue involves two things at once:

• the browser needs local network access permission: over VPN, server addresses become local network addresses, and the browser blocks requests to them. How to grant permission — here;
• connections to the Media server, including UDP, must pass through the VPN tunnel. HTTPS access to the corporate server alone is only enough for messaging — learn more.

Not Using VPN?

• Check browser permissions for the microphone, camera, and local network, then reload the page.
• Disable ad-blocking extensions, VPN and proxy extensions.
• Check the network accesses for calls — they differ from the accesses for messaging.

Nothing Helped?

Collect call diagnostics in the browser and contact your organization's support or eXpress support.

For Administrators: How to Quickly Distinguish a Network Problem from a Browser Problem

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• The problem reproduces only in the browser, while the desktop app on the same workstation and in the same network doesn't have it — this is a browser restriction, not the network.
• The problem reproduces in both the desktop app and the browser — network accesses for media traffic are blocked.
• The problem occurs only when VPN is enabled — typically, both causes are at play.
• In the browser console (Fn + F12 > Console tab), local network access blocking errors differ from network timeouts: the connection is not “hanging” but is rejected immediately.

Centralized distribution of browser permissions — in the section on browser policies.

Connection Errors, Server Issues, or Participant Removal

The issue may be related to the device, network, or server:

• Try calling from another device (via mobile or web app). If the call works, the issue is local: disable VPN, switch networks, check network access, update the app. Если проблема есть только в веб-приложении, см. отдельную инструкцию.
• If the call cannot be made from any device, there may be a server issue.

Determine the scale of the issue, collect client call logs from the app from participants who experienced connectivity problems, and contact your organization's support team or eXpress support.

For Administrator: Collecting Diagnistic Info

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If the call has already ended, collect logs:

• From client devices (participants with the issue and observers).
• Server logs (the administrator can download them via the
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Instructions for collecting logs are available here. Specify in the notes which participants encountered the issue.

Unable to Start Screen Sharing

Screen sharing is only available in the web and desktop versions of the app.

If the error Screen sharing prohibited appears, there are two possible solutions:

• All participants must connect to the organization's internal network (contour).
• Contact the administrator to enable screen sharing for external participants.

For administrators: how to enable screen sharing in an external network

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In the admin panel, under VoEx, enable the setting Allow screen sharing outside the contour.

Screen Sharing Does Not Work on Windows

In Windows, the message Allow the app to access screen recording in system settings appears on any screen capture failure, even if access is allowed in the settings. Check the following in order:

1. Open Settings > Privacy & security > Screenshots and screen recording. Turn on Let apps take screenshots and record the screen and Let classic apps take screenshots and record the screen. If this section is not available, go to the next step.
2. Launch the app without administrator rights. If eXpress is running with administrator rights, neither a window nor the screen can be shared. This happens if the app was opened via Run as administrator or is launched by another program with administrator rights.
3. If the error appears only for one window, such as Microsoft Project, share the entire screen.
4. Check screen sharing in the web version. If it works in the web version but not in the app, contact your organization's administrator.

If the required window is not in the list, restore it and turn on screen sharing again: minimized windows do not appear in the list.

If nothing helped, reproduce the error and immediately collect a diagnostic log and a call log. Send them to your organization's support team or to eXpress support.

For Administrators: Screen Sharing Works in the Web Version but Not in the App

• Check how eXpress is launched. If it is launched by a workstation shell, script, or shortcut with administrator rights, the app inherits these rights and cannot capture the screen. Configure it to launch as a regular user.
• Check AppLocker rules and other application launch control tools. They may block components that the app unpacks at startup. Allow launching from the eXpress installation directory (by default %LOCALAPPDATA%\Programs\eXpress\) and the files %LOCALAPPDATA%\Temp\*.node.

Screen Sharing Does Not Work on macOS

If screen sharing does not start, open System Preferences > Security & Privacy > Privacy > Screen Recording and grant access to the eXpress app or browser.

Screen Sharing Does Not Work on Linux

Check the graphics session type in the terminal:

echo $XDG_SESSION_TYPE

If the output is x11 — screen capture works directly; no additional configuration is required.

If the output is wayland — screen capture is performed through the PipeWire and xdg-desktop-portal system services. Permission to share the screen is granted by the user: when starting screen sharing, the operating system shows a dialog to select a screen or window. If the dialog does not appear and a black screen is transmitted:

1. Install the required packages (if missing):
   • Debian/Ubuntu/Astra: sudo apt install pipewire xdg-desktop-portal xdg-desktop-portal-gtk (for KDE — xdg-desktop-portal-kde)
   • RED OS/Fedora: sudo dnf install pipewire xdg-desktop-portal xdg-desktop-portal-gtk
   • ALT Linux: sudo apt-get install pipewire xdg-desktop-portal xdg-desktop-portal-gtk
2. Check that the services are running in the user session:
   systemctl --user status pipewire xdg-desktop-portal
   If necessary, restart them: systemctl --user restart pipewire xdg-desktop-portal, then restart the application.
3. If the issue persists, log out and log back in (required after package installation) or select an X11 session on the login screen.

The Call is Hung — It Remains Active After Participants Leave

The call/conference appears as active even though no one is in it, and it cannot be ended in the app. Contact your organization's administrator or eXpress support to force-terminate the call on the server.

For Administrators: How to Terminate a Hung Call

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In the admin panel, under Calls or Conferences, locate the hung call by searching for the conference name, chat title, participant’s name or HUID, or by using the call ID from the logs — it will have true in the Active column. Terminate it using the X button.

Audio cuts out or doesn't work when using a Bluetooth headset

To resolve the issue:

• Android 12 introduced a permission for apps to use nearby devices. Enable this permission for the app: Settings > Apps > select the app > Permissions.
• Disable the LDAC codec in the Bluetooth device settings.
• Remove the paired device in the Bluetooth settings and pair it again.

No chat history in group call or conference (room) chat on all devices

Troubleshooting instructions are available here.

Recording didn't arrive, an error appeared, or the recording has no audio or video

If an error occurred during recording transcoding, the recording didn't arrive within a day, or it plays incorrectly (no audio or video), contact your organization's support.

In your request, specify:

• approximate time of the recording;
• name of the group call or conference;
• call_id from the call/conference client logs.

For Administrators: Resolving Recording Issues

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Try sending the recording for re-transcoding: find the recording in the Call recordings section in the admin panel and click the re-encode button.

You have two days before the unprocessed recording is automatically deleted from the server's temporary folder (default value, but you can increase the retention period for unprocessed recordings using a special server environment variable — check with eXpress support for details).

Issue with the Outlook Add-In

Refer to the guides to troubleshoot the issue yourself.

Nothing Helped?

If the issue persists, contact eXpress support with the following prepared:

• Outlook version, add-in version, and logs;
• time the error occurred;
• email associated with Outlook and used to launch the add-in;
• meeting name (if the error occurred after its creation).

Low-quality screen sharing

Screen sharing quality depends on:

• sender's and receiver's network speed;
• monitor resolution;
• window selection for sharing (it's recommended to share individual windows rather than the entire screen).

Sharing is optimized for static images rather than dynamic content. Future updates are planned to improve image transmission quality.

Disconnected from conference on mobile after incoming GSM call

When connecting to a conference via mobile data (not Wi-Fi), an incoming call may block internet access. This will cause the participant to be automatically disconnected from the conference after some time.

Can't Change Audio and Video Quality Settings

This means the call settings are managed from the corporate server. For details, please check with your organization's support.

Screen Sharing on Windows Distorts Colors

This issue occurs if HDR is enabled in Windows, causing the image to look overexposed or washed out. Temporarily disable HDR before screen sharing, or share individual windows instead.

Error “Virtual Backgrounds Unavailable”

To resolve the issue, update the client app to version 3.62 or higher. If that doesn't help, contact your organization's support team so the administrator can check the system for compliance with virtual background requirements.

“Call Connection Error” or Immediately Admitted to the Conference When the Waiting Room Is Enabled

You are connecting to a conference with the waiting room enabled from an outdated version of the app — update it.

For Administrators: Enable “Lobby” in the Admin Panel

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If the lobby is not enabled on the invitee's server but is enabled on the admin's server, the invitee who joins via a link bypasses the lobby (expected behavior). You can enable the lobby in the VoEx section.

“Calls are not available on this device” | “Conferences are not available on this device” When Trying to Call

Calls are disabled in the application settings by the Vdi parameter. This is usually enabled by an administrator for environments where calls are not supported — for example, in VDI (more details). Contact your administrator or your organization's support.