"File contains invalid data" during installation.

If you receive an error message from the installer, it's almost always because of an antivirus program. Sometimes the installation file will appear to be correctly downloaded but the antivirus program has done something to it and when you try to use it, you'll see a message about "File contains invalid data". The solution to this is to temporarily disable the antivirus and re-download the file. You can scan the file after download if you need to.