Katana does not automatically search your entire computer for plugins. You must tell it where to look using : OpWrite — Katana Developer Guide - Foundry Learn
Based on common file-naming conventions and the software context, this query most likely refers to a for Foundry Katana , a professional look development and lighting tool . The "(1)" suggests it may be a duplicate or a versioned copy of a core system file or plugin . Katana (1).dll
In the context of Foundry Katana, a .dll file (on Windows) is typically one of the following: Katana does not automatically search your entire computer
A compiled C++ plugin used to modify scene graph data . Katana (1).dll