SourceTree won't authenticate with bitbucket repo

[Don Clark]

While I can log in to the bitbucket server using a browser, and my SourceTree client on Windows 10 can authenticate with the bitbucket server, my SourceTree client on Mac Sierra cannot authenticate with the bitbucket server.  I have a clone of a project on my Mac that SourceTree can see, but authentication fails when I attempt a pull.  It pops up a dialog requiring my password - I enter the same password used for the browser login, but it pops up another dialog asking for the password.  Eventually it gets to the point of telling me I have to log in with the browser and do a captcha - I successfully do that but after that SourceTree still cannot authenticate.  

I have one suspicion - since the project was cloned on my Mac my network password has changed - this is the same password used by the bitbucket server.  There appears to be no way to edit the password in SourceTree on Mac, although I was able to edit the password in the Windows SourceTree client and make this work.

[Manju]

You can remove all items saved by Sourcetree in  Keychain and try. 

Also, you can add your Bitbucket server account in Sourcetree as a hosted account in Preferences - Accounts. This gives you the ability to edit passwords whenever they change. 

[Don Clark]

Removing all source tree entries from keychain didn't solve the problem.  Adding the bitbucket server entry into SourceTree doesn't work either.  Apparently SourceTree is caching some identity information somewhere that isn't apparently editable, and the Mac SourceTree client has become unusable with Bitbucket.  Pretty sad.

[Manju]

It looks like this is a bitbucket server instance. Can you please confirm the authentication protocol and type for the account you are adding in Sourcetree?