the original file can't be found (TV episode)

I am getting this error message on my PC when attempting to watch a Downton Abbey episode I bought with the season's pass:

The TV show "Episode 4 (Original UK Version)" could not be used because the original file could not be found. Would you like to locate it?

I've spent two or three hours on this problem. I googled it. I searched the Apple support pages. I followed several different suggestions. I found where all the other files for this TV series live. Episode 4 is listed there, but when I attempt to open it, I get the error message, and the file is marked with an exclamation point. I checked my trash bin. It wasn't there. I tried to download it again, but the Apple store tells me it IS downloaded. I can watch all the other episodes. This latest one, Episode 4, just won't let me in.

I posted this problem a couple of days ago, and can't figure out how to get back to that discussion and see if anyone can help me.

I am not impressed. I want my money back. I will never buy an iTunes product again if I don't get this episode to work. There are other ways to download media. You are not the only game in town. Downton Abbey is a continuing story. Missing an episode is the same as if you took one of my books, yanked 50 pages out of the middle of it, and told me, "here, read this." Seriously annoying.