There was no endpoint at XXX that could accept the message

Adding the belwo tag solved my problem of uploading the file more than 4 MB of size.

< system.web>
<httpRuntime maxRequestLength="65536" />
< /system.web>

However just for testing purpose I tried uploading file more than 20 MB of size.
The test failed :( and the new exception I got was

"There was no endpoint at XXX that could accept the message. This is often caused by an incorrect address or SOAP action"

My Service bindings was as below

<binding name="My_Binding" closeTimeout="00:10:00" openTimeout="00:10:00"
    receiveTimeout="00:10:00" sendTimeout="00:10:00" bypassProxyOnLocal="false"
    transactionFlow="false" hostNameComparisonMode="StrongWildcard"
    maxBufferPoolSize="2147483647" maxReceivedMessageSize="2147483647" messageEncoding="Text"
    textEncoding="utf-8" useDefaultWebProxy="true" allowCookies="false">
     <readerQuotas maxDepth="32" maxStringContentLength="2147483647" maxArrayLength="2147483647" maxBytesPerRead="2147483647" maxNameTableCharCount="2147483647" />
     <reliableSession ordered="true" inactivityTimeout="00:10:00" enabled="false" />
     <security mode="Message">
      <transport clientCredentialType="Windows" proxyCredentialType="None" realm="" />
      <message clientCredentialType="Windows" negotiateServiceCredential="true" algorithmSuite="Default" />
     </security>
    </binding>

Also I had <httpRuntime maxRequestLength="65536" /> in web.config

Googling through several article, finally I found a solution. Adding the below tag in my WCF Service help me to upload document more than 20 MB of size

<system.webServer>  
     <security>    
           <requestFiltering>
                    <requestLimits maxAllowedContentLength="204800000" />    
          </requestFiltering>  
   </security>
</system.webServer>