PHP warning: headers already sent in Unknown

php error-reporting
kari.patila picture kari.patila · Mar 7, 2009 · Viewed 11.6k times · Source

I'm looking for things that might trigger the following PHP warning:

PHP Warning: Cannot modify header information - headers already sent in Unknown on line 0

Answer

kari.patila picture kari.patila · Mar 7, 2009

Turned out that it was the line

ob_start("ob_gzhandler");

that caused the warning. This has been reported and fixed in 2001, it seems, but for some reason it keeps coming back.

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