Hi already used smartGit Hg a couple of months. I have already account in bitbucket which I used already couple months already also. When I created another account in bitbucket
I was getting a similar error while authenticating with Git over HTTPS, after much frustration I uninstalled SmartGit and deleted everything in my SmartGit AppData folder.
(on Windows Delete c:\Users\{YOUR_USER_NAME}\AppData\Roaming\syntevo\SmartGit)