HTTP Handler is not working in managed pipeline mode Classic

Hi all

I am working on an application which requires to have an HTTP Handler for handling a .pdf File 

The handler's configuration in web.config file is as followed,

<system.webServer>

<handlers accessPolicy="Read, Script">
<add name="FilePdf" path="*.pdf" verb="*" type="ComplianceMonitor.TestingHandler" resourceType="File" modules="IsapiModule" scriptProcessor="C:\Windows\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64"/>
</handlers>

</system.webServer>

but the problem is that the handler is not working on classic managed pipeline mode, Did I miss something here?

As per the client requirements, we need the handler to work in Classic mode only

Any suggestions.?

Your help is most appreciated

thanks in advance