I have the exact same issue.
I'm on Vista 64, I have already 18.104.22.1681.
The exe after being downloaded just cannot be run. I have an Admin account, and even if I right-click and choose Open as Administrator, it does not work..
I don't normally have antivirus issues, but for the record I have AVG free. I have downloaded on 2 separate browsers.
I have tried installing before and after having uinstalled ADE 1.7.2, but that seems to make no difference. I have several Adobe apps (trial editions and regular editions) on my machine, with nothing giving me problems except this one.
I have just managed to solve this problem.
On the application (.exe file):
Right click, select properties
At the bottom, beneath 'Attributes' I found a security warning which was preventing it from running. Click the button and voila.
Hope that helps.
Pete, that solved my problem. Thanks. (Note: on my machine, there was a button which said "Unblock" which I needed to push.)
Please see Installing Adobe Digital Editions 2.0 in Windows Vista - http://helpx.adobe.com/digital-editions/kb/installing-digital-editions-20-windows.html for more information about how to unblock the installation under Windows Vista.
Thanks, Jeff, but it's a Windows 7 machine. Pete (Win8) answered my issues.
Thanks TdeV1. I was mainly posting this for future users facing this difficulty under Windows Vista similar to I believe Idiotprogrammer2 experienced.