Can't Listen to Podcast, file is missing

So, I had an issue with a podcast I've been listening to. For some reason, iTunes only downloaded a small part of the episode, and wouldn't play the rest. Remove download wouldn't work, it just hid the file. So I went into Windows explorer and deleted the files, hoping to fix it.

Now it won't let me redownload it, every time I try to listen to it, it just says the file is missing and to locate it, but if I try remove download, it does nothing.

Does anyone know how to rescan my library or something? Thanks.