Inside Plugin Registration Tool, you’ll find a button which says Install Profiler, Click it.
Once it is done, you will find an entry for Plug-in Profiler beneath your assemblies.
Now, go-to the step for which you want to debug your plugin and press the Profile button.
Once done, you will see a tag (Profiled) adjacent to the step.
Now go ahead and execute the plugin i.e. perform the steps in CRM that will trigger this plugin.
If the code has any errors, then CRM will provide you a log file to download; go ahead and download the file. (see screenshot below)
Now, inside Visual Studio, insert Breakpoints wherever you feel and use Attach to Process button and attach the code to Plugin Registration Tool exe. Note: Initially you will see that VS cannot find symbols so breakpoints will not be hit.
Now, go back to Plugin Registration Tool and Select the Step which you profiled earlier hit Debug button.
A new Dialog-box will be presented to you, refer to the necessary files and hit Start Plug-in Execution button.
Wait for a few seconds and you will start to see the following in Plug-in Traces window from Debug screen.
Now, switch to Visual Studio and you will see that your first Breakpoint has been hit.