n8n-io/n8n · warning · ConflictError

409

409

Error message

Cannot ${action} workflow - you have this workflow open in another tab

What it means

validateWriteLock throws ConflictError (409) when the write lock is held by the same userId but a different clientId — i.e. the same user has the workflow open in another browser tab and the action would conflict with that tab.

Solutions

1. Close the other editor tab(s) for that workflow and retry.
2. Refresh the conflicting tab so it re-acquires/releases the lock correctly.
3. Avoid editing the same workflow in multiple tabs simultaneously.

Example fix

n/a

n/a (lock holder state is server-side and changes asynchronously)

function isConflictError(error: unknown): boolean {
  return error instanceof Error && /open in another tab/.test(error.message);
}

try {
  await collaborationService.validateWriteLock(userId, clientId, workflowId, action);
} catch (e) {
  if (isConflictError(e)) { /* 409: tell user to close the other tab */ }
  else throw e;
}

When it happens

Trigger: Request supplies userId+clientId, getWriteLock returns a lock with same lock.userId but different lock.clientId; the action parameter is interpolated into the message (e.g. 'save', 'activate').

Common situations: User has n8n open in two tabs and edits/saves in one while the other holds the lock; stale tab after a refresh; multiple windows of the same browser session.

Related errors

• 423
• MCP tool " " from conflicts with
• Removed entity " " is also scheduled for update operation…
• " " is not part of this query
• The credential with ID

AI-assisted analysis of n8n-io/n8n@5ac6606e81 (2026-08-12). Data as JSON: /api/errors/2600f1fd81354aec. Report an issue: GitHub.

Appendix: source

Thrown at packages/cli/src/collaboration/collaboration.service.ts:397

		action: string,
	): Promise<void> {
		if (!clientId) {
			return;
		}

		const lock = await this.state.getWriteLock(workflowId);

		if (!lock) {
			return;
		}

		if (lock.clientId === clientId) {
			return;
		}

		if (lock.userId === userId) {
			// Same user, different tab
			throw new ConflictError(
				`Cannot ${action} workflow - you have this workflow open in another tab`,
			);
		} else {
			// Different user
			throw new LockedError(`Cannot ${action} workflow - another user currently has write access`);
		}
	}
}

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