1. If the decanter is removed for more than 30 seconds while the unit is brewing it may cause the coffeemaker to overflow. Make sure the decanter is replaced promptly after removing.
  2. The decanter may not have been properly positioned under the brew basket. Be sure the decanter is centered directly under the brew basket.
  3. Using too much coffee grounds may cause the coffeemaker to overflow.
  4. The filter may have become folded over. Make sure the filter is properly centered in the brew basket. Try wetting the edges to prevent filter collapse.
  5. The brew basket may not have been closed completely. Check to make sure the brew basket is fully closed and (on some models) latched.
  6. Using coffee that is too finely ground can sometimes result in overflow. Use only coffee that is ground for automatic drip coffeemakers.