If your packet analyzer isn’t capturing traffic correctly, dropping packets, or showing no interfaces, this guide will help you diagnose and fix the most common capture problems.
Analyzer Not Capturing Any Traffic
One of the most common issues is starting a capture session and seeing no packets at all.
Possible Causes:
- Wrong network interface selected
- Missing or outdated capture driver
- Insufficient permissions
- Promiscuous mode disabled
How to Fix It:
- Confirm the correct interface is selected
- Verify your capture driver (see WinPcap vs Npcap)
- Run the analyzer as administrator
- Enable promiscuous mode in capture settings
Dropped Packets During Capture
If your analyzer reports dropped packets, your system may be overwhelmed.
Common Reasons:
- High network utilization
- Insufficient CPU resources
- Slow disk write speed
- NIC limitations
Solutions:
- Use capture filters to reduce traffic
- Close unnecessary applications
- Capture to RAM instead of disk (if supported)
- Consider hardware capture for high-speed links
Learn how to refine traffic using our Display Filters Guide.
No Interfaces Found
If your analyzer shows “No interfaces found,” the capture driver may not be installed correctly.
- Reinstall Npcap with administrator privileges
- Ensure driver compatibility with your OS version
- Check for conflicts with VPN or security software
If you’re just getting started, follow our Wireshark Download Guide to ensure proper installation.
Inaccurate Time Stamps
If packet timing appears inconsistent, your system clock or hardware may be the cause.
- Synchronize system time using NTP
- Check CPU load during capture
- Understand software vs hardware timestamp limitations
For deeper comparison, see our guide on How to Choose a Protocol Analyzer.
Firewall or Security Software Blocking Capture
Endpoint security tools may block packet capture drivers.
- Temporarily disable antivirus for testing
- Whitelist the analyzer application
- Verify driver permissions
General Troubleshooting Checklist
- Update your analyzer to the latest version
- Update capture drivers
- Reboot your system
- Test with a simple ping capture
- Confirm network activity exists on the interface
Frequently Asked Questions
Why is Wireshark not capturing packets?
Most commonly due to incorrect interface selection, missing drivers, or insufficient permissions.
Why are packets being dropped during capture?
High traffic volume, CPU limits, or NIC constraints can cause dropped packets.
Do I need Npcap for packet capture?
Yes. Modern versions of Wireshark require Npcap for packet capture on Windows systems.