404.2 The page you are requesting cannot be served because of the ISAPI and CGI Restriction list settings on the Web server

All,

Recently we faced one error (404.2 The page you are requesting cannot be served because of the ISAPI and CGI Restriction list settings on the Web server) while accessing an application on 2008 R server (IIS 7.0). Our application is in .net framework 4.0. 

When I had seen about this error initially what ISAPI and CGI, i could not recall immediately. 

So just to give brief on this,

ISAPI : Internet Server Application Programming Interface.           

CGI    : Common Gateway Interface.

To avoid this problem, below steps were taken place. Let see it may helpful for you.

a) Go to inetmgr, (IIS)

b) Clicked on the server.

c) Double click “ISAPI and CGI Restrictions”

e) Right click of ASP.NET v4.0 (which is available from framework64 bit) -> and made it allowed.  

 f) iisreset (run  -> iisreset  )

After performing above steps, I could able to access my application with out issues.

Hope it may helpful .

Thanks,

Ravi