[MC-45109] I can use 1.7.4 but not 1.6.4

Put the summary of the bug you're having here

What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
Describe what happened here

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
3. ...

Comments 3

It worked for 1.7.4 normally but not 1.6.4 Forge.

Tech support issue, but so you know mods are not supported.

This is a technical support issue; this site is for bug reports only. For technical support please use the Mojang Support Center.

I also tried 1.7.2 and 1.6.2 and they didn't work either.