Guide
Cursor Troubleshooting: Install, Performance, Network, and Tab Fixes
Most Cursor problems trace to one of five areas: a failed install or blank startup screen, slow performance from heavy extensions or indexing, blocked network requests, Tab suggestions not appearing, or a conflicting extension. The fastest first move is usually to disable extensions one at a time and confirm your plan and connection.
On this page
Cursor won't install or shows a blank screen
Install and first-launch failures usually come down to a stuck process, a macOS security warning, or low disk space. Match your symptom to the row below; each fix is a quick reset rather than a deep repair.
- Blank screen on launch
- Quit and restart Cursor. On Mac, drag Cursor to Trash and reinstall from cursor.com/download; on Windows, run Cursor as administrator. Then run Clear Editor History from the command palette.
- macOS says the app is 'damaged'
- This is a macOS warning, not a corrupted download. Quit Cursor, force-quit any leftover processes in Activity Monitor, wait a minute, then move Cursor to Trash, empty it, and re-download. Restart the Mac if it persists.
- Low disk space
- Remove unused extensions and run Clear Editor History from the command palette.
This is covered hands-on in Tab and Inline Editing — 4 short modules, free to read.
Cursor is slow or using too much CPU or memory
Two things account for most performance complaints: an extension misbehaving, and Cursor trying to index folders it should ignore. The steps below isolate the extension and trim what gets indexed.
- 1Run
cursor --disable-extensionsto launch with none, confirm the slowdown is gone, then re-enable extensions one at a time to find the culprit. - 2Add large generated folders to
.cursorignore— for exampledist/,build/, and.next/— so the indexer skips them. - 3Make sure
node_modulesand similar dependency folders are in.gitignore; Cursor respects.gitignorewhen it indexes, so this keeps big trees out of the index.
The same extension test applies to typing lag: disable extensions one at a time, or launch with the command-line flag to type in a clean editor and confirm whether an extension is the cause.
Cursor can't connect (network errors)
Connection failures usually come from a proxy or firewall between you and Cursor's servers, or from a VPN leaving stale settings behind. Start with the built-in diagnostics, then work through the specific cases below.
Open Cursor Settings > Network > Run Diagnostics to test connectivity. If a proxy blocks HTTP/2, switch HTTP Compatibility Mode to HTTP/1.1 and restart. If a firewall blocks outbound traffic, allowlist Cursor's domains.
- Case
- Firewall blocks outbound connections
- What to do
- Allowlist
*.cursor.sh,*.cursor-cdn.com, and*.cursorapi.com.
- Case
- Remote SSH — AI features fail
- What to do
- AI runs locally and calls Cursor servers, not the remote host. Check your local internet, watch remote CPU/memory, set
ServerAliveInterval 60andServerAliveCountMax 3, and restart Cursor after reconnecting.
- Case
- DNS errors after leaving a VPN
- What to do
- Fully restart Cursor to clear inherited environment variables. Verify DNS with
scutil --dns(macOS) or/etc/resolv.conf(Linux).
- Case
- 'Suspicious activity' block
- What to do
- Often VPN-triggered. Disable the VPN, start a new chat, wait a few minutes, or sign in with Google or GitHub instead.
| Case | What to do |
|---|---|
| Firewall blocks outbound connections | Allowlist *.cursor.sh, *.cursor-cdn.com, and *.cursorapi.com. |
| Remote SSH — AI features fail | AI runs locally and calls Cursor servers, not the remote host. Check your local internet, watch remote CPU/memory, set ServerAliveInterval 60 and ServerAliveCountMax 3, and restart Cursor after reconnecting. |
| DNS errors after leaving a VPN | Fully restart Cursor to clear inherited environment variables. Verify DNS with scutil --dns (macOS) or /etc/resolv.conf (Linux). |
| 'Suspicious activity' block | Often VPN-triggered. Disable the VPN, start a new chat, wait a few minutes, or sign in with Google or GitHub instead. |
Most connection errors resolve by clearing a proxy/HTTP-2 conflict, allowlisting Cursor's domains, or restarting after a VPN change.
Cursor Tab isn't suggesting anything
When Tab goes quiet, the cause is usually your plan allowance, a blocked connection, or an out-of-date build — not a broken feature. Check these four before anything else.
- Plan allowance: Free (Hobby) accounts have a monthly Tab allowance; once it is used up, suggestions pause until the next billing cycle.
- Blocked HTTP/2: enable HTTP Compatibility Mode to fall back to HTTP/1.1, then restart Cursor.
- Outdated build: press ⌘Ctrl⇧P and run Cursor: Attempt Update.
- No connection: Tab needs an active internet connection to return suggestions.
Tab draws on your recent edits and the surrounding code, so making a few manual edits first signals your intent and sharpens what it proposes. If suggestions are slow, check your connection and disable unused extensions — VPNs and proxies add latency. You can also click the Tab status indicator in the bottom-right corner to turn Tab off for specific file types, like markdown or JSON.
An extension is breaking Cursor
Extensions that ship their own AI completions or grab keyboard shortcuts are the usual source of conflicts — other AI coding assistants especially. The three steps below find the offender by elimination.
- 1Open the command palette and run Disable All Installed Extensions.
- 2Check whether the problem is gone.
- 3Re-enable extensions one at a time until the conflict reappears — that last one is the cause.
To disable a single extension directly, open the Extensions panel (⌘⇧X on Mac, Ctrl⇧X on Windows and Linux), find it, and click Disable.
How do I report a bug to Cursor?
Cursor triages bugs from its community forum, and a good report includes a request ID so the team can trace your exact session. The steps below gather what they need and explain how Privacy ModeCursor's setting that routes requests under zero-data-retention terms so providers don't store or train on your code. changes what they can see.
Post on forum.cursor.com and include your Cursor version, operating system and version, steps to reproduce, expected versus actual behavior, screenshots for visual issues, a request ID, and any console errors from Developer Tools. To grab the request ID, open the conversation in the Chat sidebar, click the ... context menu, and choose Copy Request ID.
With Privacy ModeCursor's setting that routes requests under zero-data-retention terms so providers don't store or train on your code. on, support can only see the model used, whether tool calls failed, and backend failures unrelated to your content — not your conversation. With Share Data on, they see full conversations, tool details, and context. Privacy Mode is per-request, so changing the setting does not retroactively expose past requests. For an agent-behavior bug, temporarily enable Share Data, reproduce the issue, copy the new request ID, and send that.
Frequently asked questions
Why is Cursor so slow or using so much memory?
The usual causes are a heavy extension and over-broad indexing. Launch with cursor --disable-extensions to confirm an extension is at fault, then re-enable them one at a time. Add generated folders like dist/, build/, and .next/ to .cursorignore, and keep node_modules in .gitignore — Cursor respects .gitignore when indexing, which keeps large trees out of the index.
Why isn't Cursor Tab suggesting completions?
Check four things: whether you've used up the Free (Hobby) monthly Tab allowance, whether your network is blocking HTTP/2 (switch HTTP Compatibility Mode to HTTP/1.1 and restart), whether your build is outdated (run Cursor: Attempt Update), and whether you have an internet connection. Conflicting extensions and VPN latency can also suppress or slow suggestions.
Cursor can't connect — how do I fix network errors?
Run Cursor Settings > Network > Run Diagnostics. If a proxy blocks HTTP/2, set HTTP Compatibility Mode to HTTP/1.1 and restart. If a firewall blocks traffic, allowlist *.cursor.sh, *.cursor-cdn.com, and *.cursorapi.com. After disconnecting a VPN, fully restart Cursor to clear stale environment variables.
How do I fix the macOS 'Cursor is damaged' message?
That warning is a macOS security check, not a corrupted download. Quit Cursor, force-quit any leftover Cursor processes in Activity Monitor, wait a minute, then move Cursor to Trash, empty it, and re-download from cursor.com/download. Restart your Mac if the message persists.
How do I report a bug so Cursor can actually reproduce it?
Post on forum.cursor.com with your Cursor version, OS and version, reproduction steps, expected versus actual behavior, screenshots, and a request ID (Chat sidebar → ... menu → Copy Request ID). For agent-behavior bugs, temporarily enable Share Data, reproduce the problem, and send the new request ID — Privacy Mode otherwise hides the conversation from support.
Sources & last verified
- Cursor - Install issues
- Cursor - Performance
- Cursor - Network
- Cursor - Tab issues
- Cursor - Extensions
- Cursor - Reporting bugs
Cursor ships frequently. Facts verified against primary sources on July 15, 2026.