Do you have anything in your solution named Service1? It sounds to me like you have added a Service Client to your project (likely by accident) and did not configure it. If you added it intentionally, then you must configure it. Here is a link to the help article on the service client.
It has been a while since I have used it, but according to the article and my experience, the service client generates a dynamic assembly that you must retain and source control. If you do not have access to this assembly, you would need to re-add your service client and recreate all the settings and changes you've made to it.
No. I never added any service client to the project. I read the document you linked to (thank you) but still not sure how I go about clearning this out since I never added it in the first place and not sure where I go looking for the problem to fix it.
Following up on this, I did find some "service1" item listed in my automation items. I am sure it was something that got added when I was learning about something about the system. I deleted it, rebuilt the project and now it is not throwing errors anymore.