I tried several times. I even changed my password twice and I still can't login. I'm using the Setup Wizard, my Github username(not my email) and password, and I get the same error:
Login error
Login failed for the following accounts:
GitHub: Bad credentials
Do you still want to proceed?
I'm able to login with bitbucket with no problems... any ideas?
I'm using SourceTree 1.8.1 for Mac under OS X Mavericks 10.9.2