I open the launcher and I click playe and says "some game files are missing and can not be downloaded when the launcher ein offline mode. Connect to the Internet and try again" why? Help me

We are unable to diagnose your issue due to the lack of proper debug information. Please review the guidelines before reporting issues.
In case of a game crash, please also attach the crash log from [minecraft/crash-reports/crash-<DATE>-client.txt|http://hopper.minecraft.net/help/finding-minecraft-data-folder].

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