I tried to download forge to play some mods with my friends and the installer successfully installed forge, however I had a problem with it not showing in the launcher so I reinstalled the official Minecraft launcher and the forge installation was showing. When I launched it, it said "Failed to download file" <file name> and then showed a link. It doesn't create a crash report file in the 'crash-reports' folder and creates a .jar file in the versions folder. It seems to be useless. The initial crash report says
Failed to download file. Name: 1.12.2-forge1.12.2-14.23.2.2611.jar URL: https://s3.amazonaws.com/Minecraft.Download/versions/1.12.2-forge1.12.2-14.23.2.2611/1.12.2-forge1.12.2-14.23.2.2611.jar Filename on disk: 1.12.2-forge1.12.2-14.23.2.2611.jar Path: C:\Users\impul\AppData\Roaming\.minecraft\versions\1.12.2-forge1.12.2-14.23.2.2611\1.12.2-forge1.12.2-14.23.2.2611.jar Exists: File