Reference Problem

I have an app I am writing that will be run off of a server by multiple systems. It uses a COM object to communicate with other another system. In C# I added a reference to the COM object. When I compiled the program and placed it out on the server, it could not find the COM object. In the add references dialog box, it shows the correct path to the .exe. The COM object is located on the c:\ of each system that will be running the program. In the properties for the reference, the Path value is pointing to a .dll that is located in the path to my solution. The program runs fine on my system, so it seems it is using this .dll that I'm not sure where it came from.