Locating Outlook dll

I have my C#, Asp.net website which Opens my outlook mail item on clicking a button. I have added Microsoft.office.interop.outlook.dll version 12.0 to my bin from .NET.

While running the application, from which location it will take my dll. Either from bin or from GAC?

Because I have installed Outlook in my local machine. so I can able to run my code. But once I publish the code to Server, I could not able to run my application. It is throwing me an error '

Could not load file or assembly 'Microsoft.Office.Interop.Outlook, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

' I dont have outlook dll in my server.

Please suggest