You may get this error when you are dealing with lot of variables and trying to passing those variable to header and by a mistake you have new line in your header string.
i was getting this following error when redirecting after form submit..
“Warning: Header may not contain more than a single header, new line detected. in /home/gedforad/public_html/index.php on line 60”
So i was thinking there may be the problem with redirect it with lot of variables but it was not!
there may be you have some code like this
Or whatever code you have with lot of variable.its most common when press enter to go to new line.
here i am using location within string , otherwise actual code should be(this is also a way to avoid errors):
you will get an error if you will have some new line in your $post_url variable string.
just test your code again and remove new line in your code, you can post lot of variable through browser.