Because OWC11 is unsigned by modern standards and contains known security weaknesses, SmartScreen filters and modern antivirus software will often block the installation or execution of the control, flagging it as "potentially unwanted software."
Microsoft no longer recommends using OWC due to known security vulnerabilities and lack of updates. How to add reference to MS office web components 11.0? microsoft office web components 11.0 library download
For a developer in 2004, this library was revolutionary. It allowed the creation of complex financial dashboards and reporting tools with minimal code, assuming the end-user was running Internet Explorer on Windows. Because OWC11 is unsigned by modern standards and