Network Connection Failed Repeatedly – No Response in Diagnostics

Support Bug Reports
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1

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

Cursor suddenly becomes completely unable to connect to the internet after restarting the app.

The issue started today. Cursor was working normally last night until around 1:00 AM.
This afternoon (around 3–4 PM), after reopening Cursor, it became fully offline:

Network status shows DNS / HTTP2 / SSL = No response

Agent / Plan mode cannot work at all

No requests go through

This happens regardless of:

Network used

Cursor version installed

Other applications and websites work normally on the same machine and networks.

Steps to Reproduce

Cursor works normally the previous day

Close Cursor

Reopen Cursor the next day

Cursor shows DNS / HTTP2 / SSL = No response

All network-related features stop working

Expected Behavior

Cursor should be able to connect to the internet normally on a healthy network, and downgrading to a previous version should restore functionality.

Operating System

MacOS

Version Information

Cursor Version: 2.4.27

VSCode Version: 1.105.1

Commit: 4f2b772756b8f609e1354b3063de282ccbe7a690

Date: 2026-01-31T21:24:58.143Z

Build Type: Stable

Release Track: Default

Electron: 39.2.7

Chromium: 142.0.7444.235

Node.js: 22.21.1

V8: 14.2.231.21-electron.0

OS: Darwin arm64 24.6.0 (macOS)

For AI issues: which model did you use?

all models are not working now.

Additional Information

What I Tried

Restarted Cursor multiple times

Switched networks:

Home Wi-Fi

Public library Wi-Fi

Mobile hotspot

Verified network speed (≈70 Mbps up/down)

Confirmed other websites and apps work normally

Uninstalled Cursor completely

Reinstalled and downgraded to:

2.4.23

2.3.41

Result:
None of the above resolved the issue.
Even older versions that previously worked are now unable to connect.

Does this stop you from using Cursor

Yes - Cursor is unusable

3

Hey, thanks for the report.

The fact that even older versions don’t work suggests something external is blocking Cursor’s connections, like an antivirus, firewall, or other security software.

A couple things to try:

  1. Check the macOS firewall: System Settings > Network > Firewall. Make sure Cursor is allowed, or temporarily turn it off to test.

  2. Security software: Do you have Little Snitch, CleanMyMac, corporate monitoring software, or any MDM profiles installed? We’ve seen a similar case caused by a conflict between corporate monitoring software and Cursor: Cursor Connection Failing Only on My MacBook Pro - Machine Specific Issue

  3. Disable HTTP/2: App settings Cmd + , > search for “HTTP/2” > enable “Disable HTTP/2”

Can you share what security software or firewall you have running? That’ll help narrow it down.

4

Hi, thanks for the reply, I checked in details at diagnostic reports and have some new findings!

  • Since yesterday and continuing today (2026-02-02 to 2026-02-03), almost every time I open Cursor, macOS generates a new .diag report.

  • These are Microstackshots reports (not standard crash logs). The event is disk writes.

  • Example report shows Cursor writing an abnormal amount of data: about 8.6 GB over ~30 minutes (Writes: 8589.93 MB over 1815 seconds), exceeding the system threshold.

  • The heaviest stack in the report includes Electron/libuv filesystem write calls (e.g. uv__fs_post → write), indicating the writes come from Cursor’s Electron/Node filesystem activity.

Things I already checked / ruled out

  • macOS firewall is OFF.

  • No third-party firewall/security filtering software installed or running (I never installed any, and I double-checked).

  • No VPN and no proxy.

  • I also followed a suggestion to force HTTP/1.1 instead of HTTP/2, but it did not help (same behavior persists).

Minimal Repro

  • Create a brand-new empty folder on my Desktop (no files inside).

  • Open that folder as a new project in Cursor.

  • Only send a simple “hello” message to the built-in AI (no build/run/generation steps, no large files).

  • The disk writes .diag reports still appear repeatedly.

6

Hello, I’ve just updated the report! Also, I’d like to mention that previously, when I uninstalled the application and reinstalled an older version, I recall not deleting the library files and cache.

7

Hi, I just found out it is state.vscdb and state.vscdb.backup. They are 3.54 gb each.

9

Great job on the diagnosis. state.vscdb really shouldn’t be 3,54 GB. It’s Cursor’s state database (chat history, settings, cache), and when it balloons to that size, it can cause exactly the issues you’re seeing.

To fix it:

  1. Fully quit Cursor

  2. Delete these files:

rm ~/Library/Application\ Support/Cursor/User/workspaceStorage/*/state.vscdb*

Or delete all Application Support files for a full fresh start:

rm -rf ~/Library/Application\ Support/Cursor
rm -rf ~/.cursor*
  1. Restart Cursor. It’ll recreate clean files.

This should fix both the network connection issue and the disk writes.

I’ll pass the bloat info to the team. state.vscdb shouldn’t grow like that, it’s clearly a bug.