No, you MUST NOT whitelist CloudFlare IPs in Admin Tools. This would disable Admin Tools for everyone visiting your site through CloudFlare, i.e. everyone visiting your site. That's effectively disable Admin Tools!
Instead go to Components, Admin Tools, Web Application Firewall, Configure WAF and set Enable IP Workarounds to Yes. This tells Admin Tools that the IP of the actual visitor is not the IP your web server sees (i.e. CloudFlare's IP) but the IP CloudFlare sends in a special HTTP header when relaying the request. This way a security exception will only block the real IP causing the problem, not CloudFlare in its entirety.
If your problem persist it's possible that your host is blocking CloudFlare's access to your server. In this case please ask your host to whitelist the CloudFlare IPs on their server.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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