ProPane865

Please start your own thread, and do not extend on other threads with "I have this issue too!" type of replies.

Just click on it... It's meant for 1.12.2... just not named that way.

More info please...

I feel fairly certain that either the exclamation in the path caused the problem or the launcher isn't installed correctly. Try repairing the installation. If that does not work, then remove the exclamation in the path.

His real username does not have an exclamation. EDIT: The filename path has an exclamation in it.

The version that worked for me is 27.0.47 (Sorry, I know you said you used old versions).

Screenshots?

Just delete the version from .minecraft/versions and download a Fresh copy of Forge 1.12 for Windows and install as usual. Show screenshots if that does not work.

Download and install Forge 1.12.2, set the profile in your launcher, and put the mod jar file in the "mods" folder.

You can't use 1.14 mods with 1.12 because of the massive API changes! I bet bookshelf 1.14 is the problem.

Yes, I am coding in 1.14, and I see that they renamed the classes!

You should care, because of API changes in newer versions of Minecraft!

NVM