PHP Warning: Cannot modify header information - headers already sent by (output started at /includes/functions.php

[wads24]

Support Request Template
What version of phpBB are you using? phpBB 3.3.11
What is your board's URL? No answer given
Who do you host your board with? No answer given
How did you install your board? I used the download package from phpBB.com
What is the most recent action performed on your board? Please select your answer
Is registration required to reproduce this issue? No
Do you have any MODs installed? No
Do you have any extensions installed? No
What styles do you currently have installed? prosilver
What language(s) is your board currently using? english
Which database type/version are you using? I Don't Know
What is your level of experience? New to PHP but not phpBB
What actions did you take (updating your board; installing a MOD, style or extension; etc.) prior to this problem becoming noticeable? I checked my php error log on my server and keep seeing this error come up over and over...
PHP Warning: Cannot modify header information - headers already sent by (output started at /includes/functions.php:3035) in /includes/functions.php on line 4150
Please describe your problem. I checked my php error log on my server and keep seeing this error come up over and over...
PHP Warning: Cannot modify header information - headers already sent by (output started at /includes/functions.php:3035) in /includes/functions.php on line 4150
Generated by SRT Generator


I would appreciate any suggestions as to why this error is happening.

[Mike-on-Tour]

There seems to be a whitespace character in some file prior to the <?php first line.

[Mick]

Probably /includes/functions.php

See Knowledge Base - phpBB3 and UTF-8 without BOM

Note: I’ve not seen this error for years, I assumed PHP had sorted the BOM issue out but I was obviously wrong.

[Noxwizard]

Based on the line numbers, there should be another error message printed prior to those which is the actual error. The header errors are a result of the first error message being printed.

[Brf]

(output started at /includes/functions.php:3035)

Yes. That line (3035) in includes/functions.php is where error messages are output.
That error message is being output before the cookies are written, so it is causing the subsequent error at 4150 where the cookies are written. As Noxwizard explained, you need to fix that earlier error.

[wads24]

Thanks guys. That was it...