  We report on WIMP search results of the XENON100 experiment, combining three
runs summing up to 477 live days from January 2010 to January 2014. Data from
the first two runs were already published. A blind analysis was applied to the
last run recorded between April 2013 and January 2014 prior to combining the
results. The ultra-low electromagnetic background of the experiment, ~$5 \times
10^{-3}$ events/(keV$_{\mathrm{ee}}\times$kg$\times$day) before electronic
recoil rejection, together with the increased exposure of 48 kg $\times$ yr
improves the sensitivity. A profile likelihood analysis using an energy range
of (6.6 - 43.3) keV$_{\mathrm{nr}}$ sets a limit on the elastic,
spin-independent WIMP-nucleon scattering cross section for WIMP masses above 8
GeV/$c^2$, with a minimum of 1.1 $\times 10^{-45}$ cm$^2$ at 50 GeV/$c^2$ and
90% confidence level. We also report updated constraints on the elastic,
spin-dependent WIMP-nucleon cross sections obtained with the same data. We set
upper limits on the WIMP-neutron (proton) cross section with a minimum of 2.0
$\times 10^{-40}$ cm$^2$ (52$\times 10^{-40}$ cm$^2$) at a WIMP mass of 50
GeV/$c^2$, at 90% confidence level.
