I have faced this error while installing SubSonic(http://www.codeproject.com/KB/database/SubSonic.aspx) in my machine. I have searched on google and found the solution. This is a security issue with the Window 7.
To resolve this issue please open Command Prompt by right and ran as Administor. The move to the installer’s directory. Then run following command on command prompt:
your_InstallerName.msi
This will successfully install the installer. 
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sorry to tell u Thing u have specified is not working in my case..
in windows7 64bit platform.
By: RAHUL on August 21, 2010
at 1:07 PM
Server Error in ‘/’ Application.
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Runtime Error
Description: An application error occurred on the server. The current custom error settings for this application prevent the details of the application error from being viewed remotely (for security reasons). It could, however, be viewed by browsers running on the local server machine.
Details: To enable the details of this specific error message to be viewable on remote machines, please create a tag within a “web.config” configuration file located in the root directory of the current web application. This tag should then have its “mode” attribute set to “Off”.
Notes: The current error page you are seeing can be replaced by a custom error page by modifying the “defaultRedirect” attribute of the application’s configuration tag to point to a custom error page URL.
By: babak noori on September 23, 2010
at 12:42 PM
I have windows 7 64bits and works for me in ../program files (x86)/ folder
By: Vhutemas on February 10, 2011
at 10:25 PM