A couple weeks ago I updated SourceTree and discovered I could no longer connect to my Bitbucket repositories through SSL. This is because of the Poodle defect in SSL 3.0. (I'll skip the explanation.) The failure looked like this:
In any event, the only Atlassian forum entry on the subject gave me only partial guidance.
The problem, which took me some time to uncover, turned out to be that I had Mercurial 2.7 lurking on my machine. Uninstalling it and SourceTree, then installing Mercurial 3.0 and re-installing SourceTree, fixed the bug.
This has been a public service blog post.