DIAGNOSIS Water is leaking from the internal drain system. This model has a port for a hose on the back, and if the included rubber drain plug isn't fully seated or has failed, water will drip inside the cabinet and out the bottom.
FIX 1) Unplug the unit and pull it away from the wall. 2) Tilt it back slightly (over a towel) and look at the back, near the bottom. You'll see a circular port. 3) There should be a small, removable rubber plug pressed into this port. Check that it's pushed in all the way and sealed tightly. 4) Remove the plug and inspect it. Look for cracks, tears, or a misshapen seal. 5) If it looks good, clean the port rim, re-insert the plug, and press firmly around the entire edge. You shouldn't be able to wiggle it easily.
IF THAT DIDN'T WORK If the plug is intact and sealed but it's still leaking, the internal drain pan (which channels water to the bucket or the hose port) might be cracked or misaligned. This requires disassembly to inspect, which is a more involved repair.
HEADS UP If you ever use a drain hose, make sure it's pushed securely onto that port and that the hose runs downhill without any kinks or loops that could cause water to back up inside the unit.