Lorraine

Trying to install Windows 8 from ISO -Downloader. When clicking on either Win . 7 or 10 it allows to select what version I want. When I click Windows 8 it just clicks the whole time and nothing happens - no selection comes up. I did previously install windows 8 on my computer ( currently windows 7) but then it crashed and I have to re-install win 7 . Want to upgrade to 8 but am unable to any selection as 8 keeps flashing and clicking. Please can you assist.