With upgrade of Dynamics CRM after 2016 some time we faced different kind to strange issue.
Recently I had faced issue in one of our running plugins.
Parameter name: SandboxAppDomainHelper.Execute: The plug-in type could not be found in the plug-in assembly: MyAssemblyName
Dynamics CRM Version: –
After debugging and doing different R&D we find there is no issue in our plugin code.