Evan...I have no idea what that file is I would suggest you delete it and forget about it for now.
What you need firstly is to download and install official patch 4.08.
Then I would suggest you download the Unified Installer from this site. I gives you all you need including a version switcher which enables you to to switch versions quicker than I can type this.
You can get the official 4.08 patch for 46 here:
http://mission4today.com/index.php?name ... ls&id=1908
Download that, it is a self installing patch which will find your game installation automatically(after you click on it to activate it).
Unified Installer is here:
(The link is inoperative)
After you install the Unified Installer you can pick from some of the many other mods available here
I am aware also that there are issues with the downloaded version of 46 the solution to those issues is also on this site
I would also suggest that you stick to this site for mods, as most (all?) of them have been tested to be compatible, and I believe you are asking for trouble trying to use "mods" from some of the more dodgy sites