How to track a website redirect?

Question

open server

The site opens on the hosting, uploaded to the local OpenServer and does not open. The error is ERR_TOO_MANY_REDIRECTS.
.htaccess removed and did nothing. There is a suspicion that because of the viruses.
Tell me, can you determine what exactly (which line in which file) causes a redirect?

Answer 1

grep 'Location' /path/to/myproject/*.php
This way you will find (almost) all redirects. Most likely this will be enough to find the problem, although if it is really a virus, then they could write something like 'Loca'.'tion'this and it will be a little more difficult to track it down.
A more hardcore option is to temporarily add the headers function to the disable_functions
blacklist and see where the errors fall.