Two engineers from the Eden Prairie-based company set out for southern Ontario to do the work. They flew to Detroit and drove toward the border crossing at Port Huron, Mich.

And that's as far as they got.

"The border guard thought that whatever work we were doing, the work could have been executed by Canadian workers," said Philip Novak, a systems engineer for the company.

Such roadblocks to commerce have become a significant problem for businesses that do work on both sides of the border. The Canadian government estimates that hangups of cargo and travelers at crossings cost $16 billion annually on that side of the border alone.