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  • What were the MS-DOS programs that the moricons.dll icons were intended for?

    Posted: 2025-05-13 11:06:58

    The moricons.dll file in Windows contains icons originally designed for Microsoft's abandoned "Cairo" operating system project. These icons weren't repurposed from existing applications but were newly created for Cairo's planned object-oriented filesystem and its associated utilities. While some icons depict generic concepts like folders and documents, others represent specific functionalities like object linking and embedding, security features, and mail messaging within the Cairo environment. Ultimately, since Cairo never shipped, these icons found a home in various dialogs and system tools within Windows 95 and later, often used as placeholders or for functionalities not explicitly designed for.

    Summary of Comments ( 61 )
    https://news.ycombinator.com/item?id=43971616

    Hacker News users discuss the mystery surrounding the unused icons in moricons.dll, speculating about their purpose and the development process at Microsoft. Some suggest the icons were placeholders for future features or remnants of abandoned projects, possibly related to Cairo or object linking and embedding (OLE). One commenter links to a blog post claiming the icons were for a "Mac-on-DOS" environment called "Cougar," intended to make porting Macintosh software easier. Other comments focus on the general software development practice of leaving unused resources in code, attributing it to factors like time constraints, changing priorities, or simply forgetting to remove them. A few users recall encountering similar unused resources in other software, highlighting the commonality of this phenomenon.