Quick Answer
viber-sync.exe is safe. It's the official Viber synchronization service that runs in the background to keep messages, contacts, and settings in sync across devices.
What is viber-sync.exe?
viber-sync.exe is the Windows background service for Viber's cross-device synchronization. It coordinates data exchange between your Viber Desktop app and mobile devices, handling message history, contact status, and settings across devices.
Viber Sync operates as a dedicated background process that communicates with Viber servers to keep conversations in sync across devices. It runs under a Viber folder, uses TLS, and minimizes UI impact while enabling continuous data alignment.
Quick Fact: Viber Sync enables cross-device continuity, so new messages appear on all paired devices within moments.
Types of Viber Sync Processes
- Main Sync Service: Coordinates cross-device data exchange and session management
- Device Sync Worker: Per-device synchronization task handlers
- Notification Handler: Manages push notifications for new messages
- TLS/Network Component: Secure communication with Viber servers
- Update Checker: Checks for updates to Viber Sync components
Is viber-sync.exe Safe?
Yes, viber-sync.exe is safe when it's the legitimate file from Viber downloaded from official sources (viber.net or official app installers).
Is viber-sync.exe a Virus or Malware?
The real viber-sync.exe is NOT a virus. However, malware can impersonate legitimate files; validate digital signatures and locations.
How to Tell if viber-sync.exe is Legitimate or Malware
- File Location: Must be in
C:\Program Files\Viber\Viber Sync\ViberSync.exe or C:\Program Files (x86)\Viber\Viber Sync\ViberSync.exe. Any other path is suspicious.
- Digital Signature: Right-click the file in Explorer > Properties > Digital Signatures. Should show signer "Viber Media S.à r.l." or a trusted entity.
- Resource Usage: Normal usage is 1-12% CPU per device, 30-100 MB total memory during sync. Constant high usage is suspicious.
- Behavior: Viber Sync runs in background only while Viber is installed and syncing; persistent activity when Viber is absent is a red flag.
Red Flags: If viber-sync.exe is located outside Program Files (e.g., Temp, AppData, System32), runs without a Viber installation, lacks a valid signature, or uses resources constantly, run a full antivirus scan. Be wary of similarly named files like "viber-sync32.exe".
Why Is viber-sync.exe Running on My PC?
Viber Sync runs to keep your messages, contacts, and settings consistent across your Viber devices, and to deliver timely notifications as new data arrives.
Reasons it's running:
- Active cross-device synchronization: You have Viber on multiple devices; the service coordinates data transfer to keep chats in sync.
- Background updates and presence: It maintains contact presence and delivers updates while devices are offline.
- Startup and background tasks: Viber may launch sync at Windows startup to be ready for immediate use.
- Notification delivery: New messages push through the Viber Sync pipeline to desktop and other devices.
- Optimized data transfer: The service batches and compresses data to minimize bandwidth while syncing.
Can I Disable or Remove viber-sync.exe?
Yes, you can disable viber-sync.exe without uninstalling Viber. Disabling stops cross-device sync but may reduce notification and continuity features.
How to Stop viber-sync.exe
- End Sync via Task Manager: Open Task Manager (Ctrl+Shift+Esc), locate viber-sync.exe, and End Task
- Close Viber: Close the Viber Desktop app to stop all sync activity
- Disable Startup: Task Manager → Startup tab → Disable Viber Sync or Viber Desktop
- Disable background sync in Viber: Viber Desktop > Settings > Sync > Turn off 'Sync across devices' or similar option
- Uninstall or keep Viber: If you prefer to remove the feature entirely, uninstall Viber from Windows Settings → Apps; otherwise, leave it installed with sync disabled
How to Uninstall Viber (if desired)
- ✔ Windows Settings → Apps → Apps & Features → Viber → Uninstall
- ✔ Control Panel → Programs → Programs and Features → Viber → Uninstall
- ✔ If you only want to stop sync, disable the feature in Viber settings instead of uninstalling
Common Problems: High CPU or Memory Usage
If viber-sync.exe is consuming excessive resources, try targeted steps to reduce load while preserving essential sync features.
Common Causes & Solutions
- Large or many devices syncing simultaneously: Limit the number of devices linked to your Viber account or temporarily disable sync on older devices
- Background sync enabled during heavy activity: Pause sync in Viber Settings or disable automatic syncing when idle
- Outdated Viber Sync components: Update Viber to the latest version; check for updates in Viber or Windows Updates
- Background antivirus scanning Viber files: Temporarily pause real-time scanning for Viber directories or exclude them from scans
- Network-intensive media: Limit auto-downloads and heavy media syncing; use Wi-Fi and avoid mobile data restrictions
- Corrupted Viber Sync cache: Clear app cache via Viber settings or reinstall Viber if necessary
Quick Fixes:
1. Open Task Manager and end viber-sync.exe tasks that spike CPU
2. In Viber, disable 'Sync across devices' or schedule sync for off-peak times
3. Update Viber to latest version
4. Check firewall/antivirus exceptions for Viber processes
5. Restart Viber to reinitialize the sync state
Frequently Asked Questions
Is viber-sync.exe a virus?
The legitimate viber-sync.exe is not a virus. Verify path: C:\Program Files\Viber\Viber Sync\ViberSync.exe or C:\Program Files (x86)\Viber\Viber Sync\ViberSync.exe, and ensure the digital signature is from a trusted Viber source.
Why is viber-sync.exe running?
It runs to coordinate cross-device synchronization and timely notifications for Viber across your devices. It may start at login to ensure seamless continuity.
Can I disable viber-sync.exe?
Yes. Disable in Viber Settings > Sync, stop it via Task Manager, or disable startup; this will stop cross-device sync but may affect notifications.
Where is viber-sync.exe located?
Typically at C:\Program Files\Viber\Viber Sync\ViberSync.exe or C:\Program Files (x86)\Viber\Viber Sync\ViberSync.exe
How do I reduce Viber Sync resource usage?
Limit linked devices, disable auto-sync, update to the latest Viber, and adjust settings to reduce background activity; consider turning off background data for Viber.
Does viber-sync.exe affect privacy?
It handles cross-device data synchronization, so ensure you review Viber's privacy settings, use trusted networks, and keep software updated to minimize exposure.