I’m in my first year as a PhD student. As an undergrad and masters student I had pre-planned my entire schedule. I could look at my schedule and know exactly what class I would be taking in any given semester in the future all the way until graduation. As a PhD student I am noticing that I could plan all of my coursework in advance but noticed that many classes were unavailable. When I ask my advisor he informs me that you will have no problems. I always get the same reply. No problems. But I am having problems. I can’t register because of certain special permissions and I don’t see certain class offerings that I need for my specialization. And yet, I receive answers from my advisor such as “you won’t have any problems” or “thanks for reminding me” or “those classes are available”. I mean, this is very conflicting for me.

Should I relax? Should I be more assertive? If I am more assertive in demanding responses I feel this may hurt my progress within my program. I mean, these professors are the one’s who decide my grades and when I graduate. Any advice would be much appreciated.

I think that you have the full right to be concerned. From what is described, this advisor doesnt sound like he is doing what is really best for you which is to provide you with a candid feedback and not a pat on the back regardless of the context and content of the developments. In PhD listening to your inner voice that tells you when there is something wrong is an extremely important tactic and thats what you are doing right now. This professor doesnt sound to me like a serious professor who is taking you seriously. Since this is your first year, if you are not planning on continuing to work with him next year and on your dissertation then just to ask him any more about courses and found someone else to consult with. ther are many people who can help not necessarily from your department. If I was you, I would reconsider continuing with him next year and would make this known that I am looking for a new advisor for the next year.
Good luck