I'm having a weird problem with my PMDG installers. I just downloaded the new  747-400 v3 and  and when I try to run the installers,, but the nothing happens. I tried disabling Windows Defender, running the programs as an administrator, or in Windows compatibility mode, nothing worked. 747-400 v2 ran without a single problem... That's a really weird issue. Anybody have a solution for this ?

Interesting.  I experienced this when trying to run the uninstaller for the 747-400, then the new full installer. Neither would run (the UAC window asks if I want to run the program, I click "Yes" and nothing happens). Today I purchased the B747-8. Same story - the installer woud not run. Running the latest Windows 10 build, with all updates installed.

Other installers (and other .exe files) I've downloaded (not PMDG) run normally. It seems my system is, for some reason, flagging PMDG files downloaded even a year or two ago and somehow blocking them.

I spent several hours chasing all kinds of leads -- anti-virus/malware settings, .exe "file fixers", various registry hacks -- nothing. Although I could not solve the problem, I did find a workaround:

1. Enable the "Elevated Administrator Account" in Windows. This is easily done from an elevated command prompt: net user Administrator /active:yes

2. Sign out of your user account, log in to this Admin account, and run the installer.

3. Sign out of the Admin account, log in to your user account, and disable the Admin account (yes --> no in the command line above). I just suggest this as a best practice. 🙂

That worked for me. Hope this helps you!

Eric