Amzel01

... but there's no entry there. Seems to me there's a strong case for and undo option for the "Delete" button

it's a CAD program and it is still in C\Program Files. I have tried to reinstall/repair but it says that all software is installed, so can't get any further. I've looked in the Registry as suggested here: https://support.microsoft.com/en-us/help/247515/program-is-not-listed-in-add-remove-programs-after-installation

Thanks. It's gone from the W10 Apps and Features list as well, so not sure if any third party intaller will find it either.

I intended to uninstall, but accidentally deleted the entry from the list. Is there a way to undo that? What does deleting the entry actually do - does it delete anything from the installation other than a registry value?