Yes, some people have been turned away for a prior DUI, which the Canadian Government apparently takes pretty seriously. It depends upon what they ask you, because some individuals have not been questioned and have gone right through. Some, in the face of being turned away due to a prior DUI, have been able to pay a $240.00 rehabilitation fee. It is apparently a bit dicey up at those border crossings!
It is my understanding that after five years from the end of your probation, you can apply to the Canadian government for rehabilitation, which does involve payment of a fee. In theory, you cannot enter Canada with a drunk driving conviction before that time, and until they are satisfied that you are "rehabilitated." I have heard of people getting into Canada for work purposes earlier, but I have never seen anything substantiating that. I do not have any information as to any other countries. You may want to contact a lawyer in Windsor.
The information contained in this answer is intended to convey general information. Nothing contained in this answer is intended as specific legal advice. Although the content is believed to be accurate as to Michigan law, no guarantee is made that it is accurate and up-to-date. This is not an offer to represent you, nor is it intended to create an attorney-client relationship.
Traveling out of the US is not the problem. As you have learned, it is traveling into the other countries that can be difficult. It is up to each specific country whether they grant you admittance, so you would have to contact any country you were planning on traveling to directly.
Macy Jaggers's answer to a legal question on Avvo does not establish an attorney-client relationship. Ms. Jaggers offers everyone a free consultation to discuss their case. Feel free to call her office at 214-365-9800 to make an appointment (phones are answered 24 hours) or visit her website at www.macyjaggers.com for more information about her services and recent victories.
You would have to contact the country you are traveling to and see what the policy is.
In regards to Canada I believe I can make it so that you will not get jammed up any more.
Call my firm if interested 734-453-7806