Debug a plugin in Dynamics 365

we generally use plugin registration tool to deploy a plugins in dynamics crm

In visual studio : put a debugger

Attach to process:

• w3wp.exe – standard plugin
• CRMASyncService.exe – if the plugin is asynchronous
• Microsoft.Crm.Sandbox.WorkerProcess.exe – for sandbox plugins

Custom workflows cannot be used in the CRM online sandbox

limitation of sandboxes plugin

The limitation of not being able to call webservices and DLL’s in the GAC can be quite restrictive.

There is a solution using ILMERGE, which is a method of merging a number of different DLL’s into one DLL, which will allow you to use the plugin in a sandboxed environment.  I would be cautious about this approach because if you ask anyone who has done it, they will tell you it wasn’t easy and debugging a merged DLL can be impossible.

Here is a good article on ILMerge issues