Here are some things that might help:

  • Cloning Joplin into a subdirectory of C:\Users\YourUserNameHere\ instead of C:\Project (or maybe checking the folder permissions on C:\Project).
    • This might help if the current Windows user doesn't have the correct permissions for the C:\Project folder.
  • Running yarn install as corepack yarn install.
    • It looks like you've already fixed the corepack enable issue, but if the fix is somehow causing issues, the above might help.