# WebSocket Connection Failed During Workflow Execution

**URL:** <https://community.sparkflows.ai/t/websocket-connection-failed-during-workflow-execution/319>\
**Category:** Troubleshooting\
**Created:** [April 27, 2026, 9:20am UTC](https://community.sparkflows.ai/t/websocket-connection-failed-during-workflow-execution/319 "2026-04-27T09:20:54Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![neeraj](https://avatars.discourse-cdn.com/v4/letter/n/e47c2d/32.png) [@neeraj](https://community.sparkflows.ai/u/neeraj)\
**Post date:** [April 27, 2026, 9:20am UTC](https://community.sparkflows.ai/t/websocket-connection-failed-during-workflow-execution/319/1 "2026-04-27T09:20:54Z")

</div>

When clicking **Execute** to run a workflow, a dialog appears indicating that it could not connect to the server.  
In browser developer tools, you may see: **“WebSocket connection failed.”**

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## Possible Causes & Solutions

### 1. WebSocket Ports Blocked

- Ensure required **WebSocket ports are open** within your VPC.

- Verify **Security Groups / Network ACLs** allow inbound and outbound traffic.

### 2. Firewall or Security Restrictions

- Check if any **firewall or security agent** inside the VPC/VM is blocking WebSocket connections.

- This includes:

### 3. Browser Compatibility

- Ensure you are using a **supported browser version**.

- Older browsers may not support required **SockJS/WebSocket protocols**.

### 4. VPN / Antivirus Interference

- Disable or check:

- These can sometimes block or inspect WebSocket traffic.

### 5. Insufficient Memory

- Ensure at least **16 GB RAM** is allocated to **Sparkflows**.

- Low memory can cause services (including WebSocket handlers) to fail.

### 6. Proxy / Network Drops

- Verify that:

## Reference Documentation

For more details, refer to:  
[https://docs.sparkflows.io/en/latest/troubleshooting/websockets.html](https://docs.sparkflows.io/en/latest/troubleshooting/websockets.html)

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