Are you on Windows or Mac?
Is this a fresh install? If not, can you try downloading the latest version from https://www.sourcetreeapp.com/? Are you getting the same error after that?
Please let us know so we can pinpoint where the error is coming from.
The problem is with version 3.0.15, but on sourcetreeapp.com you can only download the older 3.0.12 version. It seems that the 3.0.15 is only slowly rolled out to users via the automatic updates.
I have now reported this issue as https://jira.atlassian.com/browse/SRCTREEWIN-11147 so hopefully someone will take a look at it.
Installing a newer Sourcetree version will not have any effect on your code, as your files are hosted on your computer, not in Sourcetree.
If you still don't want to install the new version, can you let us know if you have automatic updates enabled or disabled?
Supported Platforms macOS Windows We recently introduced support for additional hosting services such as GitHub Enterprise, GitLab (Cloud, Community Edition, Enterprise Edition), and...
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