The NA62 experiment at CERN SPS recorded in 2007 a large sample of K+→μ+νμ decays. A peak search in the missing mass spectrum of this decay is performed. In the absence of observed signal, the limits obtained on B(K+→μ+νh) and on the mixing matrix element ∣Uμ4∣2 are reported. The upgraded NA62 experiment started data taking in 2015, with the aim of measuring the branching fraction of the K+→π+ννˉ decay. An update on the status of the experiment is presented.The NA62 experiment at CERN SPS recorded in 2007 a large sample of K+→μ+νμ decays. A peak search in the missing mass spectrum of this decay is performed. In the absence of observed signal, the limits obtained on B(K+→μ+νh) and on the mixing matrix element ∣Uμ4∣2 are reported. The upgraded NA62 experiment started data taking in 2015, with the aim of measuring the branching fraction of the K+→π+ννˉ decay. An update on the status of the experiment is presented