I am currently trying to figure out my problem for hours. The last thing I know, was that I changed under Configuration -> Web -> Unsecure
the base url to https://example.com After that action I get the error "too many redirects" when I go to my website. I tried to fix it with phpMyAdmin and changed the secure_base_link and unsecure_base_link to http://example.com , but nothing works. Cleared var/cache and var/sessions too and my browser cache too. Still nothing new.
It could be Magento, it could be your web server, it could be some other well intentioned but not thought out PHP code. The first step is to figure out what URLs are leading to a redirection loop, and then through that intuit which systems are causing the redirect, and then fixing them. Here's step 1.
Use curl to trace the redirect -- the -i will include the headers.
curl -i https://example.com
Then, whatever location header is included, curl -i that until you see the same pattern as your browsers.
Then -- look at the contents of the replay below the header. Is it standard web server error messages? Magento error messages? Can you not reproduce the redirection loop, but there's some javascript in the page?
All of these will point you towards the solution to your problem -- i.e. figuring out what changes to your system's stock behavior caused the redirect loop.
