How to debug server side code in ARAS?

I have added the breakpoint 

if (System.Diagnostics.Debugger.Launch())


It hits on the method breakpoint in Visual Studio, but I can't see the code nor I can step into it either. Also attaching the error occured for reference.

Symbol data not founded for the module.

<operating_parameter key="ServerMethodTempDir" value="[path]" />

what path should I enter here?