I don't usually post about installing mods, but this time, I just HAVE to.
Whenever I try to install both OptiFine and Minecraft Forge, I always get the following near the bottom of the Development Console:
Client> 2013-07-13 19:05:49 [SEVERE] [ForgeModLoader] The minecraft jar file:/C:/Users/Windows/AppData/Roaming/.minecraft/versions/1.6.2-Forge126.96.36.1999/1.6.2-Forge188.8.131.529.jar!/net/minecraft/server/MinecraftServer.class appears to be corrupt! There has been CRITICAL TAMPERING WITH MINECRAFT, it is highly unlikely minecraft will work! STOP NOW, get a clean copy and try again!
Client> 2013-07-13 19:05:49 [SEVERE] [ForgeModLoader] For your safety, FML will not launch minecraft. You will need to fetch a clean version of the minecraft jar file
Game ended with bad state (exit code 1)
However, if I just install Minecraft Forge or just OptiFine, it works as it is meant. But together, no way.
At first, I realized this is probably some incompatibility with OptiFine and the latest Forge, so I waited until an... official release for OptiFine. The following day, OptiFine Ultra had been released officially. What made me think this would work was: compatible with Forge #789
Great! So I downloaded it, and installed with with the Minecraft Forge Installer. I believe this is Forge #789, since the file's name is "minecraftforge-installer-1.6.2-184.108.40.2069.jar" (If this is, for some reason, not Forge #789, tell me)
So, I used the installer, and put in OptiFine's files. I thought I was finally going to be able to use OptiFine and Forge (which is for Rei's Minimap, in case you are wondering). But unfortunately, I get the same error.
If anybody, and I mean anybody, knows a possible solution, please tell me!