I think I have the same problem. (When I start the game it loads for a while and then I get code 0 in the launcher)
Killing all FTBApp (ftbapp.exe), Minecraft Launcher (launcher.exe) and Minecraft (javaw.exe) processes and then deleting everything they created in "%temp%" solves the problem for me.
Annoyingly I have to do this every time I want to start a modpack.
You can also just simply delete everything you are able to after killing the processes but it's enough to delete these folders:
- .com_ibm_tools_attach
- hsperfdata_%username%
- jna-<a long number>
- mc_libs
- MinecraftLauncher
%username% is your username
<a long number> is a long number
Obviously I use Windows so I don't know exactly how to solve this on Linux or MacOS but you should be able to do the same thing there (closing FTBApp, Minecraft Launcher
and Minecraft and deleting the temporary files).
Deleting all the folders listed above is still more than you need but I didn't tried what exactly has to be deleted.
(FTBApp also creates a ".log" and ".ico" file but these do nothing to Minecraft)
I don't know for sure if this file is safe to use but for those who know what it is and understand what I did there:
If you trust me - a random guy from the internet you don't know - you can use the ".txt" file after replacing the ".txt" in the filename with ".bat" to do this.
You should NOT trust me or anyone else who tells you to execute a ".bat" or ".cmd" file as long as you don't understand what that file does because you looked at it with a text editor.
I read the rules and I didn't see a rule about ".bat" files. If they aren't allowed please tell me. I will remove the file as soon as possible.