Component Object Model (COM) Error – E_ILLEGAL_DELEGATE_ASSIGNMENT 0x80000018

In this post, you’ll learn about the error “E_ILLEGAL_DELEGATE_ASSIGNMENT 0x80000018” that is returned when working with COM based APIs or libraries in Windows.

COM Error Message


What is COM?

Microsoft’s COM stands for Component Object Model. Component Object Model (COM) is a networked, object-oriented framework for building interoperable binary software components.   Microsoft’s OLE (compound documents), ActiveX (Internet-enabled components), and other products are built on the COM base technology.

Error Description

Below is the description of this COM Error.

A delegate was assigned when not allowed.