cURL error 35 — CURLE_SSL_CONNECT_ERROR — means the TLS handshake started but never completed. It is not a certificate-validation failure (that is error 60); something rejected or broke the negotiation itself. The usual suspects are HTTPS pointed at a plaintext port, protocol mismatches, interception in the path, and a wrong proxy URL scheme. Here is how to isolate each one fast.
Error 35 is CURLE_SSL_CONNECT_ERROR: the TCP connection succeeded, curl began the TLS handshake, and the negotiation broke before a secure channel existed. The far end sent a fatal alert, reset the connection, or replied with bytes that are not TLS at all. It is distinct from error 60 (certificate verification failed — the handshake got further) and error 28 (nothing answered in time).
Failures cluster into three families. Protocol mismatch: your curl offers TLS versions or ciphers the server will not accept — typical with an outdated OpenSSL build, or with legacy flags like --tlsv1.0 or a hand-rolled --ciphers list forced in an old script. Wrong protocol on the wire: https:// pointed at a plaintext port, or a proxy hop wrongly wrapped in TLS — the plaintext reply cannot parse as a ServerHello, producing OpenSSL's famous "wrong version number". And interference: middleboxes, TLS inspection, or a target that resets handshakes from IP ranges it distrusts.
The wrapped detail narrows it fast: "wrong version number" means plaintext answered; "alert handshake failure" means negotiation was rejected; a bare connection reset during the handshake usually means something dropped you deliberately.
First confirm what is actually listening on the other end of the socket; then narrow protocol and path issues in order.
https:// against port 80 or any plaintext service fails with error 35, typically with a wrong version number detail.-x http://host:port is correct for a standard CONNECT proxy. Writing -x https:// makes curl attempt TLS on the proxy hop itself.-v and read the TLS lines — they show the offered protocol version and the exact point the handshake died.--tlsv1.2 or --tls-max 1.2. If pinning fixes it, one side's supported range is the problem.openssl s_client -connect host:443 -servername host. If that fails too, the fault is in the network path or server, not in curl.--ciphers, --curves, or legacy version flags inherited from old scripts — over-constraining the handshake is a self-inflicted error 35.With an HTTP proxy and an https:// URL, curl connects to the proxy in plaintext, issues CONNECT to open a tunnel, and only then performs the TLS handshake with the target through that tunnel. Error 35 can therefore occur at two different points: on the proxy hop, if you declared the proxy itself as https:// when its port speaks plain HTTP — or inside the tunnel, when the target kills the handshake it sees arriving from the proxy's exit IP.
That second case is the one scrapers hit. Sites defending at the network layer can reset TLS handshakes from IP ranges with poor reputation — most often datacenter blocks — before a single HTTP byte is exchanged. Your TLS stack is fine; the exit IP is the variable. Changing what the target sees, by moving to residential or ISP-grade exits or by rotating to a fresh IP, resolves resets that no client-side flag can.
The proxy URL scheme describes the hop to the proxy, not the destination. For HTTPS targets through ProxyOmega, use -x http://USERNAME:[email protected]:10000 — end-to-end TLS still protects the request inside the CONNECT tunnel. Every ProxyOmega port also answers SOCKS5, so socks5h:// is a drop-in alternative on the same port.
If handshakes fail only against certain sites and only through certain exits, you are being filtered at TLS time. Rotating residential exits on Budget Unlimited (/plan-unlimited/) or Tier-1 ISP-quality IPs on Platinum (/plan-platinum/) present consumer-grade addresses that these filters are far less inclined to reset on sight.
Through SOCKS5, curl tunnels raw TCP and your local TLS stack negotiates directly with the target. If HTTP-proxied requests throw error 35 but the same request via socks5h:// succeeds, the CONNECT layer or scheme was the culprit. Since ProxyOmega serves both protocols on one port, the test is a one-line change.
The proxy hop stays http:// while TLS runs end to end through the tunnel to the target — the standard layout that avoids self-inflicted handshake failures.
# http:// proxy scheme + end-to-end TLS through the CONNECT tunnel
curl -x "http://USERNAME:[email protected]:10000" \
--tlsv1.2 \
-sS -o /dev/null \
-w "TLS ok, HTTP status: %{http_code}\n" \
"https://example.com/"--insecure does not fix error 35 — it only skips verification. If -k changes nothing, you have confirmed the failure is at the protocol level, not the trust level.https:// makes curl attempt TLS on the proxy hop itself, which fails against a plaintext CONNECT port. Second, the target is resetting handshakes coming from that exit IP. Fix the scheme first, then test a different exit or rotation to rule out reputation filtering.https:// pointed at port 80, a service that only speaks plain HTTP, or a proxy hop wrongly wrapped in TLS. Check the URL, the port, and the proxy scheme; one of the three is speaking the wrong protocol.ProxyOmega serves HTTP, HTTPS, and SOCKS5 on every port — one endpoint, residential and ISP-quality IPs in 200+ countries.
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