Why do I get "Internal Error" popup when using Chat?

Support Bug Reports
1

image
image691×206 8.12 KB

**
Where does the bug appear (feature/product)?**
Editor, Tab & Chat (autocomplete, Composer, in-editor agent)

Describe the Bug
I keep getting an “Internal Error” popup when using Cursor Chat. The error says:
“An unexpected error occurred on our servers. Please try again, or contact support if the issue persists.”

I checked the logs and found:
[internal] Cancellation token requested for stream 8259d747-0c12-448c-a3b5-6fb87fd0b613
RetriableError: [internal] Cancellation token requested for stream 8259d747-0c12-448c-a3b5-6fb87fd0b613

It looks like the request is being cancelled, not failing on the server. But I don’t know why the cancellation happens.

Steps to Reproduce

  1. Open Cursor IDE

  2. Use Agent mode in Chat

  3. Send a message

  4. Sometimes get the “Internal Error” popup

Expected Behavior
Chat should return a response normally without showing an Internal Error.

Screenshots / Screen Recordings
(I attached a screenshot of the popup in my original post.)

Operating System
Windows 11

Version Information
IDE:
Version: 3.21.16 (user setup)

For AI issues: which model did you use?
Auto

For AI issues: add Request ID with privacy disabled
Request ID: 4cc8dfd7-c876-42e3-86d8-1bbea6def4d5

Additional Information
I was using Agent mode when this happened.
I already tried:

  • Restarting Cursor

  • Clicking “Try again”

  • Switching models

Does this stop you from using Cursor?
Sometimes - I can sometimes use Cursor

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)?

  • Editor, Tab & Chat (autocomplete, Composer, in-editor agent)
  • Terminal & commands
  • Models, pricing & API keys (availability, Auto/Max, BYOK/Bedrock)
  • MCP & tools
  • Cloud Agents & Automations (cursor.com/agents, scheduled/event)
  • BugBot & Code Review
  • Cursor CLI
  • Cursor Mobile
  • Remote (SSH / Dev Containers / WSL)
  • Account, billing & login
  • Something 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!

7

Hey @Zerun_Song! The request is reaching us and the model is replying. It’s the response stream that isn’t making it back to your machine, so Cursor cancels it after ~90s and shows that “Internal Error” (the “on our servers” wording is misleading here). This is almost always a VPN, proxy, antivirus “web protection”, or ISP holding back the streaming connection.

Try in order:

  1. Cursor Settings > Browser & Network > HTTP Compatibility Mode → HTTP/1.1, then fully quit and reopen Cursor and send a test “hello”.
  2. Still failing? Set it to HTTP/1.0 (long-polling), quit and reopen, try again.
  3. Still failing? Temporarily turn off any VPN / proxy / antivirus web protection, or try a phone hotspot.

If none of those work, run Browser & Network > Network Diagnostics and reply with the output plus a fresh Request ID. Network troubleshooting

8

Hi Mohit,

Thanks for the explanation — that makes sense.

I just want to update: after a few hours, I restarted my computer and reopened Cursor, and it’s working normally again now.

So it seems like it was a temporary network / streaming issue on my side, not a server problem.

I’ll keep an eye on it and try the HTTP/1.1 / HTTP/1.0 steps and network diagnostics if it happens again.

Thanks for your help!