Odd behaviour with FF, but not IE...

Hi. For some reason, when I try to download certain files, FireFox will bring up it's download prompt (save to disk, open with). But regardless of what I do, the OK button is disabled? I could understand this if it was an EXE file, but I am trying to download only a zip. IE let's me download the file. I doubt it is virus related (the file I am trying to download contains no binary data).

Any Help is appreciated.


Side note:
I am NOT dissing FireFox when I say this, but overall, it's pretty much the same as IE. barring one huge difference- you don't have to change the default options to stop spyware and such. IE automatically enables "Install on Demand". Thus the magic spyware installations. Just putting it out there. I use both.

BASeCamper