Win 7 Ent x64 PortableApps platform 10.0.1 not starting any application

I have been using PortableApps since last 4 years and it has always been a wonderful experience. I setup a new box few weeks back. This is 64bit platform with Windows 7 x64 installed on it.

PortableApps was working for first few days, then it suddenly stopped doing anything. The platform loads on start up, I can see applications but am not able to start any one by clicking on the menu.

Only Help->About, Settings menu options are working. I have tried setting it to run in Windows XP SP3, Windows 7 compatibility mode (both for start.exe and PortableAppsPlatform.exe) with administrative permissions but nothing is working.

PS:- I have also clean installed PortableApps platform.