Retrieving the COM class factory for component error while generating word document

Question

I am trying to edit a word document from VB.NET using for the most part this code:

How to automate Word from Visual Basic .NET to create a new document

Answer 1

It definitely sounds like a permissions problem. Are you running your code in a windows service? The service normally runs as Local System, which may not have permission to access the Word object model. Additionally, if word is already running using the credentials of some other user then your program may not be able to access it via COM using different credentials. The office applications tend to be single instance which seems to exacerbate this problem.