When NinjaTrader disconnects from your broker or data feed, it may appear as if the platform or VPS is at fault — but in most cases, the root cause is related to the network path between NinjaTrader and your broker’s servers.
This article outlines how to diagnose these issues and determine whether the problem is local (VPS-related) or external (broker-related).
Common Causes of Network Disconnections
User-Induced Disconnections: Disconnections can occur when NinjaTrader is manually shut down or restarted, whether done manually or via automated scripts or plugins. This action disrupts all active connections.
Network Path Issues: Connection issues can arise from problems along the network path between your VPS and the broker's servers. These may include routing disruptions or firewall interference.
Step 1: Check NinjaTrader Log & Trace Files
NinjaTrader maintains detailed diagnostic logs that often explain the disconnection reason.
How to retrieve your log and trace files:
Close NinjaTrader completely
Open File Explorer
Go to: Documents > NinjaTrader 8
Locate the folders named “log” and “trace”
Right-click each folder → Copy
Paste them to your desktop or any easy-to-access location
Upload the relevant .txt files in your reply to support or review them yourself
Look for messages such as:
WebSocket closed
An existing connection was forcibly closed by the remote host
Authentication failed
Repeated login attempts
Errors referencing your broker (e.g., Tradovate, Rithmic, Apex)
You can also submit these directly to NinjaTrader using their official instructions:
Step 2: Check Network Connectivity on Your VPS
To confirm whether your VPS lost network access during the disconnection:
👉 Follow this guide to check your Windows Event Viewer logs:
Alternatively, go to your QuantVPS dashboard → Monitoring tab.
If there are no periods where both inbound and outbound = 0, your VPS network was healthy, and the issue is likely with the broker or data feed.
Additionally, brokers like Rithmic may experience traffic limitations or temporary service outages during high-traffic periods. These external factors can often lead to recurring disconnection issues, especially during busy trading times.
Scheduled Maintenance
If a maintenance banner appears while trying to access NinjaTrader, it indicates scheduled maintenance controlled by NinjaTrader. These outages typically occur during weekends or after trading hours and resolve automatically once the maintenance period ends.
Step 3: Optimize Your Environment
To reduce the chances of future disconnections:
Add NinjaTrader to Windows Firewall
Open Windows Defender Firewall
Click “Allow an app through firewall”
Click “Change settings” > “Allow another app”
Browse to: C:\Program Files\NinjaTrader 8\bin
Select NinjaTrader → Allow both Private and Public networks
Flush DNS Cache
Open Command Prompt
Run: ipconfig /flushdns
Press Enter
🤝 Need Assistance?
If any part of the setup feels unclear, the QuantVPS team is happy to help. If you’d like us to verify your environment from our side, feel free to open a support ticket and get connected with the team: https://www.quantvps.com/