Cursor Agent / Chat fails with [permission_denied] HTTP 403 while api2.cursor.sh is reachable by curl

Support Bug Reports
1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Cursor Agent and Chat fail with:

Request ID: d7ced837-37d1-432e-bc6e-fce78bd681f2
[permission_denied] HTTP 403
RetriableError: [permission_denied] HTTP 403

This happens when submitting a prompt to Agent/Chat.

Steps to Reproduce

  1. Open Cursor IDE on Windows x64.

  2. Sign in to Cursor successfully.

  3. Open Cursor Settings and confirm the following settings are enabled:

    • http.systemCertificates = true
    • http.experimental.systemCertificatesV2 = true

  4. Run Cursor Network Diagnostics.

  5. Observe that the following checks fail:

    • API
    • Ping
    • Chat
    • Agent

  6. Observe that Authentication, Authentication UI, Cursor Tab, Agent Endpoint, Codebase Indexing, Marketplace, Downloads, and CDN checks succeed.

  7. Try to send a message in Cursor Chat or Agent mode.

  8. The request fails immediately with:
    Request ID: d7ced837-37d1-432e-bc6e-fce78bd681f2
    [permission_denied] HTTP 403
    RetriableError: [permission_denied] HTTP 403

  9. As an additional check, run the following command in PowerShell:
    curl.exe -I https://api2.cursor.sh/

  10. Confirm that the base endpoint is reachable and returns:
    HTTP/1.1 200 Connection established
    HTTP/1.1 200 OK

Actual Result:
Cursor Chat / Agent fails with [permission_denied] HTTP 403, even though the base api2.cursor.sh endpoint is reachable by curl.

Expected Result:
Cursor Chat / Agent should work normally after successful authentication and network connectivity checks.

Operating System

Windows 10/11

Version Information

3.9.16
042b3c1a4c53f2c3808067f519fbfc67b72cad80
x64

Does this stop you from using Cursor

Yes - Cursor is unusable

5

Hey @Ryo_Yamamura

I can see some requests on your side from after you posted! Did the issue resolve itself?

The 403 is probably not being returned from the Cursor but somewhere in your network (think a VPN or proxy that needs reauthentication).

7

Thanks for your help.

I was able to resolve the issue.

curl through the corporate proxy to https://api2.cursor.sh/ returned HTTP 200 OK, but Cursor Agent / Chat still failed with HTTP 403 when using my normal Cursor profile.

I then started Cursor with a clean user data directory:

cursor --user-data-dir "%TEMP%\cursor-clean-profile"

With the clean profile, Agent / Chat worked.

After that, I renamed my existing profile directory:

%APPDATA%\Cursor  -> %APPDATA%\Cursor.bak_20260701_115221

Then I started Cursor normally again, signed in again, and the issue was resolved.

So it looks like the cause was something in my existing Cursor profile, cached session, stored auth state, or local profile data, rather than basic network connectivity or the proxy itself.

Thanks again.