I know this is an old thread, but I hit the same issue you did, and joined the community just now to give an answer.
This is what you need to do, as this message appears on Windows 7 without service packs..
Go grab yourself Service pack 1
Then get the Offline installer for framework 4.7.2 (read down the page for mention of Windows 7) https://support.microsoft.com/uz-latn-uz/help/4054530/microsoft-net-framework-4-7-2-offline-installer-for-windows
As of this post I have installed with success 3.1.2, then upgraded to the latest 3.1.3
(I'm still using Win 7 in VMs for performance reasons)
Supported Platforms macOS Windows We recently introduced support for additional hosting services such as GitHub Enterprise, GitLab (Cloud, Community Edition, Enterprise Edition), and...
Connect with like-minded Atlassian users at free events near you!Find an event
Connect with like-minded Atlassian users at free events near you!
Unfortunately there are no Community Events near you at the moment.Host an event
You're one step closer to meeting fellow Atlassian users at your local event. Learn more about Community Events