Hi Dawei! If you're using a proxy, this issue could be related to that. The SourceTree logs could give you a hint, you can find them following SourceTree logfile location.
Have you tried updating the embedded version of Mercurial via Settings > Accounts > Mercurial tab? If the issue still persists, let us know which OS, version of SourceTree and version of Mercurial are you using so we can continue helping you. Note that SourceTree still does not support Mercurial 4.0 and above, as it breaks an authentication extension used to manage username/password credentials.
Let us know if you need anything further!
A vulnerability has been published today in regards to Sourcetree for Windows. The goal of this article is to give you a summary of information we have gathered from Atlassian Community as a st...
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