The newer "Starter" versions of both programs are free.
https://www.embarcadero.com/products/cbuilder/starter/free-download
https://www.embarcadero.com/products/delphi/starter/free-download
According to [
this page], you might be able to clear your temp files and that might help. Click on "Replies" at the bottom of the page to see more.
There is a temporary folder that the setup needs to create and if the folder is already there, it will throw that error at you. Reboot, then open the run dialog and type this in:
%userprofile%\AppData\Local\Temp
and clear the files/folders. Don't worry if you can't delete ALL of the files/folders. Afterwards, try the setup again and see if that works.