Fix for "Unable to prepare assets for download"

Credits for this fix go to u/its_just_luci and u/Shadow_Walker137 on Reddit. If you have the "Unable to prepare assets for download" error,

Please follow these instructions:

Close the launcher completely.

Download this legacy.json file: legacy.json

(VirusTotal scan results)

Navigate to %AppData%\Roaming\.minecraft\assets\indexes

Drop the file in that folder. Then try to start the Minecraft launcher.