Is it permissible for a veiled female student to travel alone to Canada to complete her university studies, knowing that she will be staying with her married and committed sister, and that her father approves of her travel?

If some scholars have prohibited a woman's travel without a mahram (definition) for obligatory Hajj and Umrah (definition), even with a trustworthy company, then it is all the more reason to prohibit her travel for study in a disbelieving country. The presence of a sister at the destination does not justify traveling without a mahram. Therefore, a woman must remain in her country until a mahram is available to travel with her. It is preferable that she seek a field of study in her own country, because disbelieving countries contain many temptations.