The redirect I see when I try to visit the /administrator URL of your site comes from a plugin. Since you have renamed Admin Tools' main.php it does not come from Admin Tools: its code no longer loads. I don't know what other plugins you may have or how they work.
Remember, system plugins are folders under plugins/system. When you rename a folder, e.g. by adding -bak
to its name, the plugin's code no longer loads. Try doing it, one plugin at a time (and then renaming it back) to find which plugin blocks you.
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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