Persistent "Unexpected error occurred" on all models

Support Bug Reports
1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Getting “An unexpected error occurred” on every request, across multiple models (Composer 2.5 Fast, Sonnet 5). Happens on both WiFi and mobile data. Already tried switching models, switching networks, logging out/in, and full system restart. Pro plan is active with no billing issues, usage is well within quota. Failed requests don’t appear in Usage log at all, suggesting they fail before reaching the model.
Request IDs:
1a9f4371-b0ac-4898-93f7-f9444f8cb024
4ad57f0b-dfcd-4949-88ae-2598c89c660d

Steps to Reproduce

Open Cursor IDE, type any prompt in Composer/Chat, and send. Error occurs immediately regardless of model selected.

Expected Behavior

The model should respond normally to the prompt instead of returning an unexpected error.

Screenshots / Screen Recordings

Screenshot 2026-07-03 205441.png
Screenshot 2026-07-03 205441.png2138×2159 101 KB

Operating System

Windows 10/11

Version Information

Cursor IDE Version: 3.9.16
Windows_NT 10.0.26200 x64

For AI issues: which model did you use?

Composer 2.5 Fast, Sonnet 5 High

For AI issues: add Request ID with privacy disabled

1a9f4371-b0ac-4898-93f7-f9444f8cb024
4ad57f0b-dfcd-4949-88ae-2598c89c660d
32f967d2-1bb3-4620-9def-e8506f6a5983

Additional Information

Issue persists after re-login and full system restart. Pro plan billing is active and usage well within quota.

Does this stop you from using Cursor

Yes - Cursor is unusable

5

Hey, thanks for the detailed report with the Request IDs. I checked on the server side and all three requests never reach the model. They fail during the connection step, so they don’t show up in the Usage log. Since there are successful requests on your account from the last few days, this isn’t a block. It’s a network connection issue, most likely related to VPN, proxy, or a firewall.

Let’s go step by step:

  1. Start a new chat. Sometimes a session gets into a bad state and keeps failing.
  2. Cursor Settings > Network > Run Diagnostics. This will show where the connection breaks VPN, proxy, or firewall.
  3. If you’re using a VPN or proxy: App Settings Ctrl+Shift+, > search HTTP/2 > turn on Disable HTTP/2, then restart Cursor. On 3.9.x this often fixes failures on restricted networks.

If it still fails after that, send a couple of fresh Request IDs with Privacy Mode off, and tell me whether starting a new chat helped. Let me know how it goes.