There's a couple of steps that we can take to help get you back up and running. Better than ever before!
Locate Discord in the local appdata folder. The easiest way to do this it to press start button + R when on the home screen. You'll see the run menu pop up:
As in the picture, locate your local appdata folder by typing %localappdata%, then hit enter. When in that screen, locate the Discord folder, open it, and rename "update.exe" to "update1.exe".
If you happen to be on an Windows 8.1 there's an extra step that you'll need to take in upgrading your .NET framework. You can do so, by making all available system updates to your OS (even the optional ones)
That should do the trick! If none of the above helps, please feel free to contact us at firstname.lastname@example.org and we'll be more than happy to assist you further.