Cant instal d2 need help

Hi there,

I just uninstal d2 to instal older patch back

The uninstal went fine then i launch the “intaller” and i had the windows asking for cd key. Using old box cd key too often (?) instead of the new one it kinda crash and now when i launch “instaler” it just say “play” instead of instal. Wich of course wont work

Pretty much when launching installer the “system” seem to think the game is already installed when it’s not and therefor only offer me the option to play

How to solve this plz?