He turned off his monitor. The error was gone. The spreadsheet was saved. And somewhere, deep in the guts of Windows, the right object library—the one that had been there all along—finally got the respect it deserved.

When developers encounter a "MISSING" error for this library, it usually means the project was created in a newer version of Office and is being opened on a machine with an older version, or the Office installation is corrupted . 1. Where to Find the "Missing" Library

If it returns 16.0 , the library is installed and functional. If you get an error, repair Office.

The Microsoft Excel 16.0 Object Library is a DLL (Dynamic Link Library) file that contains a set of COM interfaces, classes, and methods that enable developers to automate Excel tasks, create custom add-ins, and integrate Excel with other applications.