We bought our home in June of 2007. The wet bar's sink was unusable since the previous owners allowed the pipes to freeze. We have not repaired it as of yet, and the water isn't even hooked up to it.
Just this evening I noticed a foul odor coming from the sink. It smells like a cross between mildew and sewer. It almost feels like there is a breeze coming from the drain.
What might the smell be? Any thoughts on how I might be able to fix it?

If the sink hasn't been used for a while, the water in the trap may have evaporated leaving a direct line to the sewer.
Dumping a bucket or so of water may solve the problem.
I am not a plumber but that is the first thing I would be looking at.

If your not going to use the sink for a while, put about a cup of vegetable oil in the drain. It won't evaporate.

We bought our home in June of 2007. The wet bar's sink was unusable since the previous owners allowed the pipes to freeze. We have not repaired it as of yet, and the water isn't even hooked up to it.
Just this evening I noticed a foul odor coming from the sink. It smells like a cross between mildew and sewer. It almost feels like there is a breeze coming from the drain.
What might the smell be? Any thoughts on how I might be able to fix it?

The p trap is empty of water letting in sewer gas try porring some water down the sink use a gallon of water

Ron (KISS) had the best solution. Pour cooking oil down the trap and forget it. Good luck, tom