Error : Problem running workflow, Lost connection to the server

Questions
1

Describe the problem/error/question

What is the error message (if any)? “Problem running workflow, Lost connection to the server.*”

Please share your workflow:


(Select the nodes on your canvas and use the keyboard shortcuts CMD+C/CTRL+C and CMD+V/CTRL+V to copy and paste the workflow.)
```Error: Lost connection to the server
    at L (useRunWorkflow.ts:106:14)
    at R (useRunWorkflow.ts:386:41)
    at async O (useChatState.ts:182:20)
    at async h (useChatMessaging.ts:124:20)
    at async Object.g [as sendMessage] (useChatMessaging.ts:201:4)
    at async H (Input.vue:263:19)

## Share the output returned by the last node

<!-- If you need help with data transformations, please also share your expected output. -->

## Information on your n8n setup

* **n8n version:** Cloud
* **Database (default: SQLite):** 
* **n8n EXECUTIONS_PROCESS setting (default: own, main):**
* **Running n8n via (Docker, npm, n8n cloud, desktop app):**cloud
* **Operating system:**strong text MacOS - Tahoe 26.3
1 Like
2

Hi @Royal Just clear your browser cache or try it in incognito mode that would make it work!

3

Hi @Royal!
This can happen due to temporary network instability, refreshing the page, switching tabs for a long time, VPN issues, browser extensions, or long-running executions. If the workflow continues running or completed successfully, then the issue was only a temporary UI disconnection. If it consistently fails with this message even for very simple workflows (for example, just a Set node), then it could indicate a broader connection issue, and contacting n8n Cloud support would be appropriate.
As a best practice, avoid relying on the active editor session for long-running workflows. Instead, trigger the workflow and monitor its progress through the Executions tab.

4

Hey, could you share a bit more about your setup — are you self-hosting (Docker, npm, etc.) and what version of n8n are you on? Also knowing what nodes are in the workflow that’s failing would help narrow this down, the “lost connection to server” error can mean a bunch of different things depending on the context.