  We present limits on the lens flux of OGLE-2007-BLG-224 based on MagAO
imaging taken seven years after the microlensing event. At the time of the
observations, the lens should have been separated from the microlensing source
by 292 mas. However, no new sources are detected with MagAO. We place an upper
limit on the lens flux of $H>20.57$. This measurement supports the conclusion
of Gould et al. (2009) that the lens in this event should be a brown dwarf.
This is the first test of a prediction based on the terrestrial microlens
parallax effect and the first AO confirmation of a sub-stellar/dark microlens.
