I was using forge 10.12.0.1047 for MC 1.7.2, and I updated to 10.12.0.1056. But since then forge always crashes! I also tried the recommended version of forge! Also tried going back to 10.12.0.1047. And also tried this: https://www.youtube.com/watch?v=MqPLZIjmHlM but all with no success. Tried deleting the libraries and assets folders, but that also didn't work. Tried deleting all my mods and removing the JVM Arguments. Nothing worked... Here is the log in the launcher: (It didn't make a crash report...) http://pastebin.com/6a2z8hwm

I can however, after running 1.6.4 vanilla again, run the latest and recommended 1.6.4 forge. (I don't know why I had to run vanilla again, propably because I deleted the assets and libraries.)

Looks to me like you have a coremod that it is trying to load that is not for that version of minecraft.

Sadly the debugging shown in the console log is not the full log {its actually in a file in the logs folder}

So I can't tell you exactly what coremod it is. but ya.. thats what it looks like.

I don't think it was a coremod, since my old coremods folder is empty and I didn't have any mods in the mods folder... But here is my fml-client-latest.log: http://pastebin.com/DQAe2nAq Or should I upload a different log?

Interesting reading the log we have:

 

btj=[btj : btj => net.minecraft.client.gui.GuiMainMenu (true) size 13887]

[18:58:06] [main/DEBUG] [FML/]: Runtime patching class btj (input size 0), found 1 patch

 

Caused by: java.lang.NullPointerException

        at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:192) ~[guava-15.0.jar:?]

 

This tells me that your vanilla minecraft jar is corrupt/edited some how.

Delete versions/1.7.2

and versions/1.7.2-Forge10.12.0.1056

 

Re-run vanilla .1.7.2 to get a clean jar

Then rerun the Forge installer.

Will try!

(About 14 hours after posting this... I can't try earlier...)

Also, I think I should mention that each time I run the game, it tries to download a lot of files, and succeeds...

YESS!!! It works!!! I wonder how it happened though...