Ok. That's not entirely true. Let me explain:
I fresh installed Windows 10 on a brand new motherboard and disk. I installed Opera v72.0.3815.400 and copied my opera files from my old computer (it crashed) to my opera directory users<user name>\appdata\roaming\Opera Software\Opera Stable and eventually got it to run. I saw all my old bookmarks, etx. I set up my startup tabs, etc. and then installed drivers for my motherboard. This involved several reboots. When Windows came back up, Thunderbird (one of the programs set to run when on boot up) started but Opera did not (it was also set to start on boot up). After I finished installing all the drivers and tools, etc. I tried to run Opera from the desktop icon and then by double clicking the launcher in users<user name>\local\programs\opera. The "spinner" flickers briefly and then nothing. I tried re-installing Opera (during the install it said "upgrade" on the button to start it) to no avail.
I followed instructions I got elsewhere that directed me to download another install file and install it in a directory off the desktop (unfortunately I've lost the directions I followed). After I did the install, I realized the instructions were designed to allow someone to package the Opera files and send and send them back for investigation. What I found when I did that is that it seems to run fine for me. Normally the file you download to install Opera is OperaSetup but this time I got Opera_72.0.3815.400_setup_x64 in case that helps identify what and how I downloaded it.
I am logged in a local account, rather than a Microsoft account, and I am the administrator. My local account and my Microsoft account that I had to create when I installed Windows are the only accounts on this machine.
How do I get a "normal" Opera installation to run?