Unable to unistall/install Knime platform

Hello. I tried to upgrade from 4.7.8 to 5.2.5, but it was unsuccessful, because the extensions could not be installed. Unfortunately, 4.7.8 was uninstalled before 5.2.5. I tried to use recovery from Windows, but it would not help, because Knime had not started at all. I would like to install 4.7.8, but I encountered this problem:

I pressed yes, but there was another message:

In the end, how to uninstall it and install. And I am also afraid that I lost all my workspaces.