Browsers will only do up to 20 redirections. After that they throw an error. A backup usually needs more than 20 steps. Each step results in a redirection. So if your backup needs more than 20 steps you end up with a browser error.
It's best to use either wget or cURL to test that the URL is correct. Even better, use the Schedule Automatic Backups page which takes all guesswork out of the equation by giving you the correct URL for the currently selected backup profile. That's why I implemented this feature a few years ago. I didn't want to consult my documentation all the time to construct the URL. I'm just as lazy as the next person :)
Nicholas K. Dionysopoulos
Lead Developer and Director
🇬🇷Greek: native 🇬🇧English: excellent 🇫🇷French: basic • 🕐 My time zone is Europe / Athens
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