The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

C API Functions That Can Be Called Only from a DLL or XLL

This content is outdated and is no longer being maintained. It is provided as a courtesy for individuals who are still using these technologies. This page may contain URLs that were valid when originally published, but now link to sites or pages that no longer exist.

The C API provides 15 Microsoft Office Excel callback functions that can only be called by using the Excel4, Excel4v, Excel12, or Excel12v functions (or by one of these functions indirectly using the Framework functions Excel or Excel12f). This means they can only be called from a DLL or XLL.