Minecraft 1.10 Not Switching To Forge

1) Select your Forge profile and Edit Profile.

2) In editation, be sure you have those values right:

  • (OPTIONAL, but VERY USEFUL) Game directory : It is VERY good to store different versions in different folders, because they conflict with each other (1.9 with 1.8, vanilla with Forge etc) - the thing is that even one mutual config with different values inside can stop the game from launching - that is why you should put there some custom directory, for example I have .minecraft/ForgeProfiles/<version>
  • (OPTIONAL) Forge installer will always override "Forge" profile, it is good to rename the profile if you will install more versions in future (also it is good for tracking what version is what)
  • CHECK YOUR VERSION selection. This can be very crucial. If there is selected "Use latest version", then new released version of the game just overrided the one you were using. If you want to have Forge in that profile, reselect it to the build you want. THIS alone can do the thing you describe, there won't be anything else to setup that will affect this.

When you create new profile, you do it by duplicating your actual one. If that one had the "latest" selection, there it is why the new one has it, too.

As you can see, this whole thing is usable for ALL versions, you can select beta builds or pre-releases the same way, as Forge. If you used Forge Installer, you will have corresponding Forge versions just in the selection as any other versions.

Here is a picture of mentioned and working setup:

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