pittrek said:

What's the exact error message? Also did you type in the password or did you just highlighted it in your browser and pasted it? Because if you've done it this way you could e.g. copy an additional space or line break after the password

Here's the exact message:

Error code 5 using "unrar" Write error. No permission? No space left?

The password is never copy/pasted, I made sure it was typed in correctly. I don't think space is an issue, as i've still got a few gigs left free on my hardrive.