Bug FTB Infinity Evolved won't launch

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New Member
Nov 16, 2019
So I am trying to play FTB Infinity Evolved but it won't launch, I am currently using the twitch app to launch the modpacks but when I try to launch FTB Infinity evolved I get the launcher open but when I click play I get an error.
Failed to download file, the file contents differ from what was expected.
Name: jopt-simple-4.5.jar
URL: https://libraries.minecraft.net/net/sf/jopt-simple/jopt-simple/4.5/jopt-simple-4.5.jar
Filename on disk: jopt-simple-4.5.jar
Path: C:\Users\(me)\Twitch\Minecraft\Install\libraries\net\sf\jopt-simple\jopt-simple\4.5\jopt-simple-4.5.jar
Exists: File
Can I maybe get some in resolving this issue?