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phperror-reporting

PHP warning: headers already sent in Unknown

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

Solution

  • 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.