header errors

[reggie_styles]

When trying to access private messages I get the following errors.

Warning: Cannot add header information - headers already sent by (output started at c:\apache\htdocs\header.php:32) in c:\apache\htdocs\includes\sessions.php on line 251

Warning: Cannot add header information - headers already sent by (output started at c:\apache\htdocs\header.php:32) in c:\apache\htdocs\includes\sessions.php on line 252

Warning: Cannot add header information - headers already sent by (output started at c:\apache\htdocs\header.php:32) in c:\apache\htdocs\modules\Private_Messages\index.php on line 1701

Also I installed SpChat and when attempt to create a chat room I get the following error:

Warning: Cannot add header information - headers already sent by (output started at c:\apache\htdocs\header.php:32) in c:\apache\htdocs\modules\SPChat\inc\functions-phpnuke-only.inc.php on line 27

Since they all appear to be header erros I assume, it's the same problem causing all the errors.

Any suggestions as to how to correct this?

[planetsim]

These errors are all output more than likely an error has occured before one of the header functions (setcookie,header,session_start,etc) has been called.

[edit]
How to fix it?
Im not sure. But check for errors before anything that i stated above, otherwise ill need to see some code.

[tsinka]

Hi,

if there is no other error message in front of the header error messages then you most likely have empty lines or lines with white spaces outside the php block in include files. Make sure that the include files start with <?PHP at the very beginning and with ?> at the very end. Also make sure that there is no output inside the php code in the include files.

PHP can only send headers if there hasn't been any output before.

Thomas