Nav "Unable to Calculate"??

Hey guys, on my way home today my NAV kept giving me an error of "unable to calculate" i tried different states, addresses, etc. still nothing. You guys ever hear of this?

The only time I've seen that was when I entered an "impossible" address. For example, trying to get routing to the visitor's center at the radio telescope at Arecibo, Puerto Rico. Since I'm in Massachusetts, there's no way to get there from here. OTOH, if I put in a a restaurant on one of the islands off Massachusetts (Nantucket or Martha's Vineyard), the system handles it fine, including taking me to one of the ferry terminals.

I think I saw this once when picking an address from my address book that the Navigation didn't like. Entered it manually and then it worked.

Was a while ago so not 100% sure if the same error message.