Have you made sure that your window unit is leaning at a slight angle to cause the water condensation to drip on the outside of the home?
Again, I am assuming that this is a window unit.
Like Billy stated, is your drain hole clogged? If so this can be quickly fixed. Is the condensation pan rusted through?
For the water to drip on the inside quickly tells me that the unit is level with the ground or tilted and leaning toward the inside of the home.
Put a level on the outside box or container. See what the bubble is doing. Then shim it to create an angle.
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