One of my Windows 7 PCs running Avast Pro now has Avast Secure Browser after a recent update. But another one, though showing as up to date, still has the old SafeZone browser, on which Bank Mode has stopped working. I downloaded Secure Browser and tried a manual installation, but that does nothing - no window pops up although there’s a process for it visible in Task Manager, apparently using CPU time. What might be stopping this from installing?
On the system that has the SafeZone browser still installed, I’d suggest that
you do a clean install of Avast which should remove everything and start things over
with a clean slate. Clean Install of Avast:
https://goo.gl/4Ptzkf
If you need additional help with the Clean Install, watch this:
https://youtu.be/p-h3myRD51A
Thanks for that, Bob. Did all that. Safezone has gone, but the new Secure Browser is nowhere to be seen 
By the way, Backup/Restore configuration doesn’t restore the license! Good job I thought of taking a screen dump of the licence code.
Backing up is for your personal settings not your license. A clean install doesn’t include the Secure Browser.
You can install it from here, https://www.avast.com/secure-browser
I have tried that. A splash screen appears for a while then goes away; nothing installed. By the way another Windows 7 PC under the same licence now has both the new Secure Browser AND the Safezone browser, which didn’t uninstall itself when Avast updated itself.