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my friend has LG G3, recently updated to Android 6.0 Marshmallow and he gets -504 error code when he tries to install official Facebook app. I even tried to download .apk and tried multiple version but no progress. It doesn't looks like it's a gateway problem and he's pretty desperate. I looked at some answers and tried removing cache etc. but nothing has solved the problem. I look for any help. Thanks very much for any reply. -Feldrod

marked as duplicate by Firelord, beeshyams, Matthew Read Mar 7 '16 at 5:26

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  • Have you tried uninstalling Facebook, rebooting the phone, and re-installing it from the Play Store? – DukeSilversJazz Feb 21 '16 at 16:50
  • He can't install Facebook anyhow. He just has Facebook Messenger and that's all. He wants Facebook app. – Feldrod Feb 21 '16 at 17:34