Class not registered Error

Question

Running an application from Visual Studio 2012 on 64-bit computers, displays the following error message:

Retrieving the COM class factory for compon

Answer 1

I had run into the same problem. I added reference of Microsoft.Office.Interop.Excel COM component's dll but Office was not installed on my system it wont give compile time error. I moved my application to another system and ran it..it worked successfully.

So, I can say in my case it was the system environment which was causing this issue.