The error message in question is quite deceptive. The true problem is that in IIS7 and above, a file upload limit has been imposed by IIS, causing this mysterious "404" error.
The solution is to simply raise this limit in IIS manager to a level that is more sensible. On the command prompt, issue the following command:
%windir%\system32\inetsrv\appcmd set config "Default Web Site/
A default IIS7 configuration limits the file upload to a number shy under 30mb.
Given the more locked down nature of windows with IIS7 or newer, you would need to execute this command with administrator privileges