There are hundreds of questions you could ask to determine a job candidate’s fit for an ASP.NET related position. Characteristics of a good candidate include high comfort level, skill level, and an in-depth understanding of essential and advanced development concepts.
The interview questions below make a good primer for screening employees working in the .NET framework. That said, this list will just get you started. The best interview questions will grow from the specific job offer, ideally identified by those already working in that department and on related tasks.