Plugin Registration Rules in CRM 2011

I wrote this post a while back but never published it! With the introduction of Sandbox in CRM 2011, plugins can be registered in CRM Online in isolation, which introduces a whole new set of validation and rules for registering plugins. I have created the following decision graph which can be helpful in understanding the plugin registration process and limitations on the CRM server:


Additionally, there are these general rules that apply to all plugins:

• Plugin assemblies must have a strong name (either fully signed or delay signed).
• The strong name of a plugin assembly (and its types) excluding the version build and revision numbers must be unique in the CRM organization.
• Workflow custom activities are not supported in sandbox mode (isolation).
• Sandboxed assemblies can only be registered in Database.
• Only sandboxed assemblies can be registered in CRM Online.