Unable to install FFXI from Steam "Class not registered" AND unable to e-mail support

I tried to submit an e-mail through support, however it tells me to fill out required fields (even though I filled out every field).

Issue:

I am unable to install Final Fantasy XI: Ultimate Abyssea Edition from Steam. I had uninstalled it, and was planning on reinstalling it.

However, after re-downloading it from Steam, when I try to open it, it tries to open the POL viewer, and gives the error "Class not registered" and shuts down.

I uninstalled it, and then reinstalled it, but still get the same error.