Hi Yusoof, there's a compatibility issue with SourceTree and Hg v4, that the developers are currently investigating. This could be related to this bug SRCTREEWIN-7172. You can watch it to receive further updates or add a commment if you have any question. In the meantime you can use HG 3.7.3, which is the version embedded with SourceTree.
Hope this helps!
Supported Platforms macOS Windows To make using Sourcetree as simple yet powerful as possible we embed (bundle) dependencies such as Git, Git LFS, and Mercurial. We strive to keep these...
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