[▲ Vercel Community](/) · [Categories](/categories) · [Latest](/latest) · [Top](/top) · [Live](/live) [Discussions](/c/community/4) # How to fix Vercel Invalid Configuration error with Cloudflare Proxy enabled 9 views · 1 like · 6 posts Psenarathne 5198 (@psenarathne-5198) · 2026-04-01 · ♥ 1 Hi everyone, I’m facing an `Invalid Configuration` error on Vercel for my production domain. I am using Cloudflare as my `DNS` provider. ## Problem The error appears specifically when I enable the `Cloudflare Proxy` (Orange Cloud). When the proxy is disabled (DNS only), it works fine. > **Error: Invalid Configuration**  ## Questions How can I keep the `Cloudflare Proxy` enabled while avoiding this error on Vercel? Are there specific `SSL/TLS` settings or `CNAME` configurations I should check? Thanks! Pauline P. Narvas (@pawlean) · 2026-04-02 · ♥ 1 I recommend checking out this guide: https://vercel.com/kb/guide/cloudflare-with-vercel Psenarathne 5198 (@psenarathne-5198) · 2026-04-08 you suggested to disabled proxy in cloudflare ? Pauline P. Narvas (@pawlean) · 2026-04-08 · ♥ 1 Yes, as the guide suggests: > Using reverse proxies like Cloudflare will limit Vercel's traffic visibility for security measures, introduce latency that degrades performance, and create cache management issues that may affect reliability. We [do not recommend](https://vercel.com/guides/can-i-use-a-proxy-on-top-of-my-vercel-deployment) using a reverse proxy in front of Vercel. Psenarathne 5198 (@psenarathne-5198) · 2026-04-08 Thanks for the clarification. I understand Vercel’s recommendation to disable the proxy, but I have a specific reason to keep Cloudflare enabled for my 18 domains. The main issue I’m facing is that my websites are **crashing frequently** with **Error 526 (Invalid SSL)** and sometimes **Error 524 (Timeout)** when the proxy is on. Could you please clarify: 1. Since Cloudflare is a **‘Verified Proxy Lite’** (https://vercel.com/docs/security/reverse-proxy)provider, shouldn’t Vercel automatically handle the SSL/TLS handshake even with the proxy enabled? 2. How can I ensure Vercel correctly renews the **ACME challenge** for SSL certificates while Cloudflare Proxy is active to prevent these 526 errors? 3. Are there any specific firewall or rate-limiting settings on Vercel’s end that might be triggering these crashes when traffic comes through Cloudflare’s IPs? I really need to stabilize these 18 domains without losing Cloudflare’s features. Any advanced configuration tips would be appreciated. Pauline P. Narvas (@pawlean) · 2026-04-08 [quote="Psenarathne 5198, post:8, topic:37446, username:psenarathne-5198"] I have a specific reason to keep Cloudflare enabled for my 18 domains. [/quote] I'd love to learn more! From the docs you referenced: > We do not recommend placing a reverse proxy server in front of your Vercel project as it affects Vercel's firewall in the following ways: > > * Vercel's CDN loses visibility into the traffic, which reduces the effectiveness of the firewall in identifying suspicious activity. > * Real end-user IP addresses cannot be accurately identified. > * If the reverse proxy undergoes a malicious attack, this traffic can be forwarded to the Vercel project and cause usage spikes. > * If the reverse proxy is compromised, Vercel's firewall cannot automatically purge the cache.