HTTP Error 500.19 - Internal Server Error issue with iis

I am getting following error from my hosted site

HTTP Error 500.19 - Internal Server Error
The requested page cannot be accessed because the related configuration data for the page is invalid. 
Detailed Error Information
 Module   ProtocolSupportModule 
 Notification SendResponse 
 Handler ExtensionlessUrlHandler-Integrated-4.0 
 Error Code 0x800700b7 
 Config Error Cannot add duplicate collection entry of type 'add' withunique key attribute 'name' set to 'X-UA-Compatible'  
Config File \\?\C:\inetpub\wwwroot\abc\web.config 
Requested URL http://abc:80/Test 
Physical Path C:\inetpub\wwwroot\abc 
Logon Method Not yet determined 
Logon User Not yet determined 
Config Source
 54:            <customHeaders>
 55:                <add name="X-UA-Compatible" value="IE=edge" />
 56:            </customHeaders>

I gave the permission to the IIS_USR also in security and allow the windows authentication. Any idea to fix this

It looks like you may have duplicate key's in your configuration file based on: duplicate collection entry of type 'add' with unique key attribute 'name' set to 'X-UA-Compatible'

Search for "X-UA-Compatible" in your configuration file and make sure there is only one entry with this name.

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