Hi @pacman00700 and Welcome to the forum!
There is a filter applied on the file input to ensure the given file extension is set to .passbolt.
If you download the right kit from the browser extension, it should be already named with a .passbolt in the end and should be fine.
Here, maybe the file has been renamed after the initial download or maybe it’s not the expected one (as it’s not the same as the recovery-kit you download the first time you setup your account).
On your user profile, maybe the menu “Desktop app setup” is not activated and you couldn’t download the right file. You can follow this link if you don’t have that menu Windows application developer edition v0.5.0 🚀