strawberrytea

That helps! Thank you so much! And @DaemonUmbra@diesieben07, here's the complete installer log. https://gist.github.com/KRCoolJohn/2dcd992fd9aff2d4e9d5b71e1fd70ee0 Thanks again!

Not so sure about how to run it from the commmand line? Could you pls teach me how exactly? Thanks anyway?

It just open it with WinRAR, that's my pc's default way to open a .jar file?

My double clicking isn't run it but open it?

I can't see that either?It seems the way you talked about means run the installer with a launcher, but I ran it with java se binary?

Just the installer itelf?

That's wield, I don't see any .log file in the same folder?

I'm sorry but I think I don't really know how to find the entire file, I just copy them in the installer and paste them.

https://gist.github.com/KRCoolJohn/7d229db3d0e0d096599f2286d98677a4 There you go! Thank you so much

Upload fliled. I can't deal with the '-200' problem lol, any other options?

When I try to install the recommanded Forge 31.1.0 to 1.15.2's server, it just shows me this error: And I have tried to delete the folder it said, or redownload the installer, but it still doesn't work. Help pls, thanks:)