Yes, I had this problem Monday, when I went to use my mill after sitting for three years. I ended up putting a 1/2” rod in where the draw bar goes and gently hitting with a hammer. The arbor came out, there was no rust or crud, just a good tight fit.
I was careful to make sure the rod was larger diameter than the draw bar as to not mess up the threads.
Good luck.
Bob
Tucson, Az.?
Bob W.