We are having problems with our sink draining - when I run the garbage disposal, the water will drain away, but it doesn't otherwise. This happens both when the dishwasher runs and when water is run from the faucet.

We tried using baking soda and vinegar/hot water to see if it was a blockage that would break up, but that didn't seem to work and we don't want to use anything like Liquid Plummer.

I'm not especially plumbing savvy, so with any suggestions, I probably need them spelled out step by step.

Thanks for any help!