I download the camera raw 6.7 update so I can view Canon 5D Mark III raw files in CS5. It's a zip file. It downloads, but the .exe file is blank or just a bunch of text. I've re-downloaded several times and get the same result.
I just downloaded the file myself from this link: http://www.adobe.com/support/downloads/thankyou.jsp?ftpID=5373&fileID= 4999
The files seem fine, and they installed fine, so there's nothing wrong with Adobe's data.
Zip contains integrity protection; you should not be able to unzip the contents at all if your download of the zip file was in any way corrupted. But if all else fails you could try clearing your browser cache and re-downloading the file.
How are you checking that "the .exe file blank or just a bunch of text"? I assume you're talking about the AdobePatchInstaller.exe, right?
Note that you MUST unzip the entire package contents into a folder on your hard drive before attempting the install.