Outdated browser data breaks the verification handshake.
Cloudflare is a service that protects websites (including ChatGPT) from bots and malicious traffic. When you try to log in, Cloudflare runs a small script in your browser to verify you are a human. If your browser blocks this script—often due to an ad blocker, privacy setting, or firewall—the process fails, and ChatGPT displays this error. Outdated browser data breaks the verification handshake
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<button onclick="location.reload()">⟳ Try again</button> or firewall—the process fails