I'm using an installation of Windows 8 Enterprise 64bit from TechNet. I finally got around to activating my software and I received the following error message - "Code: 0x8007007B Description: The filename, directory name, or volume label syntax is incorrect."
It turns out the issue is pretty simple. There is a default license key that is baked into the software, you just need to change that key and input your key that you got from TechNet, MSDN, etc. and then activate it with that key in place.
1. Pull up the "Run" dialog box
2. Enter "SLUI 3" (no quotes)
3. Enter your true license key in the window that pops up
4. Hit "Activate" button and you are done!