Questions about get H1B1 visa

I made appointment in Toronto , Canada and I received a confirmation letter. In the letter it says:
1. I need to show the tie with my home country. I have been US for more than ten years, how could I should the tie? what kind material I need to prepare?
2. "Most visitors to Canada are denied visas.... if you are not resident of Canada". I will have a visitor visa if I go to Toronto.
Does anybody has same letter and same situation? Did anybody get denied visa?

Thanks