Crash caused by missing git dir

SourceTree crashed to desktop on startup. On looking at the sourcetree.log file (attached), I noticed this line repeated many times...
2015-08-29T11:13:23: Could not obtain git dir, D:\Projects\Tutorial is not a git repo.
I then created that folder and launched again without problem. Apparently it's not handling deleted folders gracefully in the FileListViewManager...
at SourceTree.View.FileLists.FileListViewManager.DetermineIfStagingIsSupportedByDvcs(IFileListContainerViewModel parentFileListContainerViewModel) in C:\projects\bitbucket.org\atlassian\sourcetreewin-prod\SourceTree.Api.UI.Wpf\View\FileLists\FileListViewManager.cs:line 62