"Open Resource Pack Folder" button doesn't work; cannot manually install either

Clicking the "Open Resource Pack Folder" button does nothing. (None of the buttons that launch external programs work for me; not sure if it's related so I made a separate issue for that.) I haven't been otherwise able to identify the appropriate folder for installing resource packs. I have followed the wiki's instructions for directly loading a resource pack, but the \.minecraft\resourcepacks folder does not exist. Manually creating it & pasting the resource packs into the folder does not make them appear under available resource packs in-game.

Minecraft is installed on a separate drive from the OS, if that's relevant.