Are you installing SourceTree in an offline environment? Unless I'm mistaken, that functionality was removed post 1.8.x.
That said, this Answer looks to have a workaround:
4.5.1 .net Framework installed on my machine and i have a physical (not virtual) machine Win 7 Professional 64bit installed.
For a time ago I had installed sourcetree and while i was trying to update i started to get this error. Then uninstalled SourceTree but now i can not reinstall it
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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