Chat error "Connection failed"

Support Bug Reports
1

Where does the bug appear (feature/product)?

Cursor 3.8.1

Describe the Bug

I’m experiencing a persistent error after updating Cursor to 3.8.1. Every time I try to use the chat/agent feature, I get the following error:

Connection failed. Please try again, or contact support if the issue persists

I’ve tried restarting Cursor but the issue persists. The Web version works fine though.

Steps to Reproduce

  1. Open Cursor
  2. type a prompt
  3. The error appears immediately

Expected Behavior

The chat/agent should work normally without errors.

Operating System

Windows

Version Information

Version: 3.8.11 (user setup)
VS Code Extension API: 1.105.1
Commit: e56ad3440df06d22ca7501e65fd518e905486ef0
Date: 2026-06-18T01:40:18.333Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 40.10.3
Chromium: 144.0.7559.236
Node.js: 24.15.0
V8: 14.4.258.32-electron.0
xterm.js: 6.1.0-beta.256
OS: Windows_NT x64 10.0.26100

For AI issues: which model did you use?

All models

For AI issues: add Request ID with privacy disabled

Request ID: 8cd8ca72-cf04-481c-9061-e00fddf54f2d

No resource accessor found for composer: bc3f99f9-3174-4ea9-9636-fc6cd9654238
Error: No resource accessor found for composer: bc3f99f9-3174-4ea9-9636-fc6cd9654238
at jXm.streamFromAgentBackend (vscode-file://vscode-app/c:/Users/XXXXXX/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:24426:5853)
at jXm.getAgentStreamResponse (vscode-file://vscode-app/c:/Users/XXXXXX/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:24426:22754)
at DIe.submitChatMaybeAbortCurrent (vscode-file://vscode-app/c:/Users/XXXXXX/AppData/Local/Programs/cursor/resources/app/out/vs/workbench/workbench.desktop.main.js:12054:740)

Additional Information

  • OS: Windows
  • Cursor Version: 3.8.1
  • User: hkim02

Does this stop you from using Cursor

Cursor works in web version, but with this issue

2

Hi there!

We detected that this may be a bug report, so we’ve moved your post to the Bug Reports category.

To help us investigate and fix this faster, could you edit your original post to include the details from the template below?

Bug Report Template - Click to expand

Where does the bug appear (feature/product)?

  • Cursor IDE
  • Cursor CLI
  • Background Agent (GitHub, Slack, Web, Linear)
  • BugBot
  • Somewhere else…

Describe the Bug
A clear and concise description of what the bug is.

Steps to Reproduce
How can you reproduce this bug? We have a much better chance at fixing issues if we can reproduce them!

  1. …
  2. …
  3. …

Expected Behavior
What is meant to happen here that isn’t working correctly?

Screenshots / Screen Recordings
If applicable, attach images or videos (.jpg, .png, .gif, .mp4, .mov)

Operating System

  • Windows 10/11
  • MacOS
  • Linux

Version Information

  • For Cursor IDE: Menu → About Cursor → Copy
  • For Cursor CLI: Run agent about in your terminal
IDE:
Version: 2.xx.x
VSCode Version: 1.105.1
Commit: ......

CLI:
CLI Version 2026.01.17-d239e66

For AI issues: which model did you use?
Model name (e.g., Sonnet 4, Tab…)

For AI issues: add Request ID with privacy disabled
Request ID: f9a7046a-279b-47e5-ab48-6e8dc12daba1
For Background Agent issues, also post the ID: bc-…

Additional Information
Add any other context about the problem here.

Does this stop you from using Cursor?

  • Yes - Cursor is unusable
  • Sometimes - I can sometimes use Cursor
  • No - Cursor works, but with this issue

The more details you provide, the easier it is for us to reproduce and fix the issue. Thanks!

6

hey @hkim02, could you try running a network diagnostic from the settings? also, a potential quick fix would be to switch to a lower version of http, base is 2.0, but in your setup it could be better to be in 1.1 or 1.0, hope that fixes your issue

8

Hi, attached diagnostic message. My http version is currently set 1.1, and the issue still persists when I changed to 1.0

Cursor Network Diagnostic Results.txt (4.8 KB)

9

oh, I just check, and indeed, it doesn’t seems like a network issue, this seems more like a stale/corrupted chat, have you try to launch a new chat instead of replying to old ones? btw, if you dont want to lose the context of said chat, you can just refference them by using the “@” and clicking on the past chat button and then choosing the chat you wanted to continue, there may be other component playing in this bug but for now try this and tell me if that solves it for you

12

Hey @hkim02,

Thanks for the diagnostics - they actually rule out the network. Your Chat and Agent connection checks both pass (tokens streaming through fine), so the path between Cursor and our servers is healthy. The one SSL flag is just your corporate network inspecting encrypted traffic with its own certificate, and since your Chat/Agent checks still succeed through it, that’s not what’s blocking you here.

So this isn’t your network or your account, and @Tom_Coustols is right that it’s a stuck chat rather than a connection issue. The No resource accessor found for composer error happens when the agent can’t tie a specific chat to an open project folder, so submitting in that chat fails immediately — the request never actually leaves your machine, which is why the web version keeps working.

To get unblocked:

  1. Make sure a project folder is open in the window (File > Open Folder) rather than an empty window.
  2. Start a brand-new chat and use that one. The stuck chat won’t recover, but its contents are still there, so copy out anything you need first.

This is something we’ve been seeing from other users on 3.8.11, so it’s a known one on our side. If a brand-new chat still fails with a folder open, reply here and I’ll take a closer look.

13

I can confirm the agent works, which is great, only that I had to re initialize the workspace (the chat history is still available, so no big deal). Thank you!