Hi, I'm trying to upload a build from with butler, using the tutorial in the manual. However, no matter what I try I am getting this error - creating build on remote server: itch.io API error (400): /wharf/builds: invalid target (bad user)
Any help? Thanks!

Show us the exact command you're trying to run and we can tell you what's happening.

The error message is being explicit in this case: In order to upload you need to specify a target which is a combination of username & channel. You specified an invalid username (either you typed it wrong, or it's for an account you don't have permission to upload to)