how to do this? like, where to find the old mod folder?I have found the fix for this issue. The old version of the mods when updating to newer versions. you need to wipe the old mod folder and the game will start as per normal. This is a bit of a workaround until the team figures out a way to remove the older mods when updating too a newer versions of the packs.
how to find the mod that is acting up? also, this is my first time attempting to use FTB/downloading any mods in general so i dont have any old mods.Fist click on the three dots of the mod that is acting up, to bring up more details on the mod in question, then click on the button open folder to see the instance for that mod and then delete the mod that is acting up, then redownload the mod which should clear up the instant crash at launch