SourceTree Enterprise: "failed to check login for user"

[Helen]

I installed SourceTree Enterprise and attempted to login to my local Bitbucket Server installation. The login fails with the message "failed to check login for user [{username}]".

The log has the following entries:
ERROR [timestamp] [1] [SourceTree.Exceptions.RemoteHostException] [.ctor] - Insufficient authentication credentials
ERROR [timestamp] [1] [SourceTree.Exceptions.RemoteHostException] [.ctor] - Failed to check login for user [{username}]

The root URL ( https://{server}.{domain}/{context}/ ), username and password are the same ones I use when successfully logging into Bitbucket in Internet Explorer on the same PC.

My username does not include any special characters such as the '@' symbol.

I have tried the suggestions in the following:
https://community.atlassian.com/t5/Sourcetree-questions/Getting-this-error-quot-Something-went-wrong-while-attempting-to/qaq-p/805220
https://community.atlassian.com/t5/Sourcetree-questions/Looking-for-more-details-on-login-error/qaq-p/802237

What additional authentication credentials am I supposed to provide, and how?

Software versions:
- Windows 7 Enterprise
- Internet Explorer 11.0.51
- SourceTree Enterprise 2.5.5
- .Net Framework 4.7.1

[Helen · Accepted solution]

Bug report here: https://jira.atlassian.com/browse/SRCTREEWIN-8743

[Helen]

This bug report is now marked as resolved and should go into version 3.0.3!

[Shusen Yi]

I have the same problem. This this Oct 17, 2019. Almost a year passed still no answer.

[James Griffin]

I had the same issue, searched and tried many suggestion to resolve but none worked for me.

My problem was simple, but not immediately obvious - my username contained a space, eg. "John Smith". I changed my username in bitbucket server to just "John" and then I could login successfully with source tree.

If Bitbucket allows you to create a username with a space, and also login to bitbucket with a space in the username, source tree also should.