I have created a WordPress theme and I have tested it in localhost , it doesn't have any error. But when I uploaded it in the host, in most of pages I see this error:
Warning: Cannot modify header information - headers already sent by (output started at /home2/dekadesi/domains/dekadesign.ir/public_html/wp-content/themes/dekadesign_v2/functions.php:1) in /home2/dekadesi/domains/dekadesign.ir/public_html/wp-includes/pluggable.php on line 1179
I checked space in wp-confing.php and functions.php but my problem is not solved. I need functions.php file, I don't know what should I do.
Thanks for your helps , I talked to my web hosting manager and they start output_buffering in my host . then problem solved !
Please add ob_start(); at the top of the functions.php file, issue will be resolved.