Really Bad Mod issues help me please

[Nhataley]

I have a very mad and i mean very very very very BAD mod issue i have downloafed the too many items mod and i only put it on to my 1 survial and then i went on another one beecause i have 2 and i still had it? and i am afraid that i will have it on opticraft then i wont be able to play cause i am banned for modding so please get back to me i love OptiCraft and dont want to get banned.
 Sinceraly,
 NHataley

[bhoughton]

Just delete your minecraft.jar and reopen

[TarynMai]

OR. Open minecraft, go to options, then click force update. That should fix it.

[Mr_Mr_Mr]

What I do, is I rename minecraft.jar's that have mods on it to minecraft-mods.jar and I use the vanilla one to play on opticraft. When you are not on opticraft, name that to minecraft-legit.jar and name the minecraft-mods.jar to the original name, minecraft.jar. To get an original minecraft.jar, rename your current one to minecraft-mods.jar and just force an update.

I never play single player anymore, so I don't need to do that. But when that new rule came in, I did that.