Sorry to hear it. There are only 2 possible solutions, neither of which are guaranteed...
a. Upgrade to V18. The route calculations are sigificantly improved over the older V17. V18 is a dramatic upgrade though, so upgrade only if you're sure. You can always downgrade, but I would say why go through the trouble. Here are the screenshots of V18.
b. If you're running on an outdated NavTech Map 6, time to get a new one.
One other idea...
If you're being taken in circles and going nowhere, try switching the route type from Fastest Route to something else.
My instinct is to say you found a bug in the map software.
a. Upgrade to V18. The route calculations are sigificantly improved over the older V17. V18 is a dramatic upgrade though, so upgrade only if you're sure. You can always downgrade, but I would say why go through the trouble. Here are the screenshots of V18.
b. If you're running on an outdated NavTech Map 6, time to get a new one.
One other idea...
If you're being taken in circles and going nowhere, try switching the route type from Fastest Route to something else.
My instinct is to say you found a bug in the map software.