foutmelding: Cannot modify header information

[BrianGT]

• Adres van je forum: http://www.hondacommunity.nl/forum
  Event. modificaties op je forum:geen
  Wanneer ontstond het probleem?2 dagen geleden spontaan
  phpBB versie:3.0.12
  
  Heb je onlangs iets veranderd aan je forum? Nee, geen veranderingen
  Wat is het probleem?

foutmelding waardoor er niet meer ingelogd kan worden.

Ik krijg boven aan het forum de volgende foutmelding:

Code: Selecteer alles

[phpBB Debug] PHP Warning: in file [ROOT]/includes/session.php on line 1042: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/session.php:1)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/session.php on line 1042: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/session.php:1)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/session.php on line 1042: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/session.php:1)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4763: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/session.php:1)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4765: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/session.php:1)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4766: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/session.php:1)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4767: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/session.php:1)

Gebruikers kunnen niet inloggen. Mijn hosting zegt dat ze niets veranderd hebben. Waar moet ik zoeken?

[El torro]

Het lijkt veel op deze melding:
https://www.phpbb.com/community/viewtop ... &t=2163875

Krijg je een andere melding als je inlogt in het beheer?

[Paul]

Wat staat er op regel 1 van includes/session.php?