Initially these questions should be open and broad to allow (potential) users to define the problem space. These can change as needed as we get more information and want to focus on certain themes.
If you are conducting research, feel free to provide enough background to help focus the questions in the domain without leading the interviewee towards certain answers.
What are the types of activities you perform in your role?
Talk through some of the problems you experience in performing these activities?
Describe the types of technology you use for these activities? Are there any things about them that stand out as sometimes frustrating? Any that stand out as positive?
If I wanted to offer you an application to help you solve these problems, what would be the minimum features you would need to start using it?