This week, Microsoft started pushing an update to Windows 8.1 and unsupported Windows 7 PCs that installs its new Chromium-based Edge browser. The browser does not replace Internet Explorer.
Restarted Windows with firewall off, nothing.
Checked BITS and it was already set correctly and running.
Weird, I can install any other browser but not this one.
A year ago, a ghacks.net article suggested only the Canary build was compatible with Windows 7 and 8.1. Not sure this would work for you as this is a dated article but you could consider installing the Canary build of chromium Edge.