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https://nishantrana.me/2018/03/12/solved-system-argumentnullexception-value-cannot-be-null-parameter-name-sandboxappdomainhelper-execute-the-plug-in-type-could-not-be-found-in-the-plug-in-assembly-in-dynamics-365/
Solved - System.ArgumentNullException: Value cannot be null.Parameter name: SandboxAppDomainHelper.Execute: The plug-in type could not be found in the plug-in assembly in Dynamics 365