Python shell works in Vasari 2.5, but not in Revit 2012

What steps will reproduce the problem?
1. Install Revit Python Shell from Setup_RevitPythonShell_2012_r139.msi
2. Open Revit 2012. The attached message appears.
3.

What is the expected output? What do you see instead?
There should be Revit Python Shell icon in Revit Add Ins. Instead is the 
message as on the attached screenshot

What version of the product are you using? On what operating system?
Revit 2012, Vasari 2.5, WINDOWS 7, MS NET 4.0, Iron Python 2.7.3

Please provide any additional information below.
The Python Shell works for Vasari 2.5(installed from 
Setup_RevitPythonShell_Vasari_TP2.5.exe), but the one installed from  
Setup_RevitPythonShell_2012_r139.msi does not work for Revit on the same 
computer (message attached). Actually this is not a problem specific to Python 
Shell, but also to SOME (but not all) other external applications for Revit 
2012 (for ex. Dynamo). The message is always same as the attached one. And it 
happened to me on two different computers - in my office at the faculty 
(installed and configured by the the faculty IT team) and on my home computer 
(installed by me of course).

Original issue reported on code.google.com by mar...@netvigator.com on 17 Aug 2012 at 4:14

Attachments:

[revit cannot load ext. application.jpg](https://storage.googleapis.com/google-code-attachments/revitpythonshell/issue-15/comment-0/revit cannot load ext. application.jpg)

architecture-building-systems / revitpythonshell

Python shell works in Vasari 2.5, but not in Revit 2012 #15