Hello Hairy (and anybody else with the same problem),
I am sorry to re-up this topic even after weeks from the original posting, but - having recently noticed that I had the same problem myself, and being information about a solution lacking or incomplete - I came up with a working workaround for Windows 10 editions that support Group Policy Editor (gpedit.msc).
This means - to my knowledge - that it won't be officially supported by Home Edition. However there are all over the Web more or less letigimate and/or working procedures to emulate the behaviour of gpedit.msc on otherwise unsupported platforms. I have not personally tested the procedure on Home edition, so I can't help here if it doesn't work as expected.
In addition to that, I have no idea why the graphical interface doesn't work as supposed, nor I know how to make the GUI work. I just wanted to make SmartScreen configurable somehow.
That said, the procedure unfolds as follows (I try to be as clear as possible):
- Be sure to be logged in as a user that can escalate privileges to Administrator (if not, do it);
- By pressing (Windows logo key) + (R), open the Run prompt;
- Type in 'gpedit.msc' (without quotes) and press (Enter) or click the 'OK' button - UAC prompt may appear: grant the required privileges;
- On the menu bar, from the 'View' menu select 'Detail';
- In the sidebar on the left, navigate through the menus as follows:
Local Computer Policy -> Computer Configuration -> Administrative Templates -> Windows Components -> Windows Defender SmartScreen -> Explorer; 6. In the main window on the right double click on the policy called 'Configure Windows Defender SmartScreen'; 7. At the top/left of the window there is a menu of entries selectable with radio-buttons.
7a) If you are experiencing the problem outlined, selecting 'Not configured' just leaves the situation as it it, that is the 'Off'
entry in the Windows Defender GUI panel (i say this as you may want at some time to revert the changes - who
knows!);
7b) If you want to change the setting, select instead 'Enabled'. Then, just below the menu, the 'Options' drop-down list will
become available. From that list, select:
7b.i) 'Warn' that matches with the 'Warn' option in the GUI panel, or
7b.ii) 'Warn and prevent bypass' which matches with the 'Block' option in the GUI panel.
That's it!
I hope it will be of some help to somebody - at least. Let me know if it worked.
Have a nice day!