Chainsaws

I have a model 350 18" chain saw that I do not frequently use. Even though it usually starts after 6-8 pulls and runs without problems. Last week I used it and again with no problem until it was refueled. The fuel mix was with new gas that was mixed with a fuel stabilizer and preformed successfully with other 2 cycle devices but the saw would not start. The spark plug was checked to insure it was working properly which it was. My question is what else might be causing it's reluctance to start.