How to Import a Converted .mrpack ZIP into MultiMC

MultiMC's .mrpack support is partial — older builds will refuse the format entirely. Converting to ZIP solves this universally.

Steps

Create a new instance
Click Add Instance in MultiMC, choose the matching Minecraft version, and install the mod loader (Fabric / Forge).
Open the .minecraft folder
Right-click the instance → Minecraft Folder. This is the equivalent of .minecraft for this instance.
Extract the converted ZIP
Drop mods/, config/, and any other folders from the ZIP into the instance's Minecraft folder.
First launch
Hit play. Allocate enough RAM (4–8 GB for medium packs) in instance settings.

If you see a Java version warning, MultiMC ships its own Java picker — point it at Java 17 (1.18+) or Java 21 (1.20.5+) as required by your loader.