I’m encountering persistent connectivity issues with Cursor 1.0.0, while version 0.5 continues to work without any problems in the same environment. This is happening for an update from 0.50 to 1.0 or a clean install.
I renamed folders (not deleted):
C:\Users\user\.cursor
C:\Users\user\AppData\Local\Programs\cursor
C:\Users\user\AppData\Roaming\Cursor
Bug Summary
DNS resolution is successful and consistent (both IPv4 and IPv6) for api2.cursor.sh and marketplace.cursorapi.com.
Connection fails within the Cursor 1.0.0 app itself, despite external tools resolving correctly.
Verified across multiple DNS resolvers (local, Cloudflare, Google 8.8.8.8).
No firewall, proxy, or host-level blocking is in place.
Running over a TLS 1.3-VPN, fragmented packets, IP geolocation in AWS Netherlands.
Packet Capture Highlights (sanitized)
Wireshark outside the Cursor seems working:
Query: A, AAAA -> api2.cursor.sh
Response: CNAME chain → api2geo → api2direct → multiple A records (e.g., 52.206.197.22)
Query: A, AAAA -> marketplace.cursorapi.com
Response: Multiple valid A records (e.g., 54.86.196.189, 35.169.198.175)
TLS Handshakes: Attempted to multiple IPs (e.g., 172.67.126.242, 93.123.102.179)
TCP ACKs & TLSv1.2 Application Data seen, but client does not complete session.
This appears to be a client-level regression or configuration or account-level issue introduced in Cursor 1.0.0. Anybody confirming this, or know the fix for the issue?
Thanks in advance for any insights or patches you can provide!
C:\Windows\System32>curl.exe --trace-time -v https://api2.cursor.sh
* Host api2.cursor.sh:443 was resolved.
* IPv6: (none)
* IPv4: 35.168.50.176, 52.3.18.101, 54.224.119.200, 3.229.32.167, 3.218.217.15, 34.232.130.202, 54.88.83.216, 18.206.37.223
* Trying 35.168.50.176:443...
* schannel: disabled automatic use of client certificate
* ALPN: curl offers http/1.1
* ALPN: server accepted http/1.1
* Connected to api2.cursor.sh (35.168.50.176) port 443
* using HTTP/1.x
> GET / HTTP/1.1
> Host: api2.cursor.sh
> User-Agent: curl/8.13.0
> Accept: */*
>
* Request completely sent off
* schannel: remote party requests renegotiation
* schannel: renegotiating SSL/TLS connection
* schannel: SSL/TLS connection renegotiated
< HTTP/1.1 200 OK
< Date: Thu, 12 Jun 2025 17:01:24 GMT
< Content-Type: text/plain
< Content-Length: 132
< Connection: keep-alive
< vary: Origin
< access-control-allow-credentials: true
< access-control-expose-headers: Grpc-Status, Grpc-Message, Grpc-Status-Details-Bin, Content-Encoding, Connect-Content-Encoding, traceparent, backend-traceparent, x-amzn-trace-id, x-request-id
<
Welcome to Cursor. From 0.305.4386-main-152376e9fa906b16dd948e443808d728d6fcd3e4 (j7fi13k3x4irqdiuccgudq) in 0.011941000120714307ms.* Connection #0 to host api2.cursor.sh left intact
Why do we have connectivity on the terminal or any other place, but the Cursor could not find the api url? For the record, proxy settings in Cursor and VS Code are empty and version 0.50 is working on these settings.