MultiMC is not up-to-date and does not list the most current versions of Forge (or Fabric) and flatout says there are no versions of Forge available for 1.17 (but there are). I want to bypass MultiMC's built-in "install forge" feature and just manually install using Forge's installer. The default path for the Forge installer is the Mojang Launcher folder:

C:\Users\Client\AppData\Roaming\.minecraft

But I alter it to the following to install into the MultiMC instance instead:

C:\Program Files\mmc-stable-win32\MultiMC\instances\1.17.1\.minecraft

But Forge installer says the "directory is missing a launcher profile, please run the minecraft launcher first". This is a brand new 1.17.1 MultiMC instance but I already launched it to make sure it was functional before trying to install Forge. I also tried creating an instance with 1.17 instead of 1.17.1. 

So the Forge installer requires the offical Mojang MC launcher and cannot install into MultiMC? Please advise. Thank you!

  I was afraid of that. I was hoping Forge installer could bypass it. Thank you for the quick reply. 

Hi @Areolata im just made my MultiMC minectaft 1.18.1 manually work with forge.

you have to make a txt file and paste this to it.

</>

{
  "minecraft": {
    "version": "1.18.1",
    "modLoaders": [
      {
        "id": "forge-39.0.75",
        "primary": true
      }
    ]
  },
  "manifestType": "minecraftModpack",
  "manifestVersion": 1,
  "name": "my forge minecraft",
}

</>

Ahen change it to .json file and compress to zip.

After creating a new instance with it everything should work.