My GE dishwasher (5.5 years old) works fine -- most importantly it drains all the water at the end of the cycle. No problem.

The problem is at random times the dishwasher, which hasn't been run in days, will fill with water on the bottom. The water appears clean/clear. There can be 2 inches of water, and it gets all over my floor when I open the dishwasher.

I have no idea why this is happening and why it's so random as to when it occurs. My plumber checked it out and said all the plumbing looks fine and I don't have any disposal or drain issues.

Any thoughts about what could be going on would be appreciated.