Minecraft Launcher

You should ALWAYS make backups before uninstalling.

As with any other piece of software, updates may go wrong for many reasons, including but not limited to: the launcher, the hardware, your custom configuration, the mods you added... and, rarely, FO as well.

Installer

1. Open the Minecraft Launcher

2. Click on Installations

3. Hover over the Fabulously Optimized installation

4. Click on the Folder button

5. If you had selected Use a different .minecraft folder for this version? during installation, delete the fabulously-optimized-x.x.x folder

6. If not, delete the mods and config folders

7. Open the versions folder

8. Delete all folders which start with fabric-loader-

9. In the Minecraft Launcher, hover over the installation

10. Click on the three dots button

11. Click on Delete

12. Click on Delete

Manual

1. Open the Minecraft Launcher

2. Click on Installations

3. Hover over the fabric-loader-x.x.x installation

4. Click on the Folder button

5. Delete the mods and config folders

6. Open the versions folder

7. Delete all folders which start with fabric-loader-

8. In the Minecraft Launcher, hover over the installation

9. Click on the three dots button

10. Click on Delete

11. Click on Delete