Surprise surprise... Windows 2019 server installation needs a repair (processor drivers just won't install after I moved my Windows disk back and forth from server to server). So I started a repair upgrade of Windows 2019 to... Windows 2019. Which FAILS because Windows Setup complains about SandboxIE and that I should manually remove it... I haven't used that program for years, and I'm already on Windows 2019 to begin with... :| regedit.exe search showed nothing. IOBit Uninstaller & Windows Programs did not find anything. File find on my complete disk (including hidden folders and system folders) showed 0 results for an installed SandboxIE BUT it did find my old torrent and backup installers in my OneDrive sync folder.... Could it be that Windows Setup searches my OneDrive folder, sees filenames with sandboxie and decides to halt the installation all together...? It can't be, right??

Wrong. Removing those files and those files alone (basically, torrent + extracted setup folders) fixed it. The installation files were counted as INSTALLED programs...!

Next step: the actual upgrade... Wish me luck....! Sigh

For now... Peace!

Devvie