An account you have access to or no? Does it work under that account?
I do have complete access to that account, and the game does work there.
To be clear, there is also another game under that account that does work on mine, so the Family Share feature does work with other games.
There is a section of the FAQ that deals specifically with that error:
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-Error 'The folllowing folders are in a state of partial install'
If you are running the game from a shortcut on your desktop, delete it and recreated from within Steam.
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I gather that did not work?
I do not run the game through a shortcut, I do it directly through Steam. Creating a new shortcut through Steam and using it doesn't help. I tried the other sections of the FAQ up to and including "The Purge" and none of them fixed the issue.
Quoting admiralWillyWilber,
Wow I got this error message I couldn't fix it. I finally had to have someone work on myc Hopefully you.get it fixed. Try your hidden administrator account.
I just tried that. It didn't help, but thank you for trying to help too.