  MACHO-96-BLG-5 is a microlensing event observed towards the bulge of the
Galaxy with exceptionally long duration of $\sim 970$ days. The microlensing
parallax fit parameters were used to estimate the lens mass $M=6^{+10}_{-3}$
M$_{\odot}$ and its distance $d$ which results to be in the range 0.5 kpc - 2
kpc. The upper limit on the absolute brightness for main-sequence stars of the
same mass is less than 1 $L_{\odot}$ so that the lens is a good black hole
candidate. If it is so, the black hole would accrete by interstellar medium
thereby emitting in the $X$-ray band. Here, the analysis of an {\it XMM} deep
observation towards MACHO-96-BLG-5 lens position is reported. Only an upper
limit (at 99.8% confidence level) to the $X$-ray flux from the lens position of
$9.10\times 10^{-15}$-- $1.45\times 10^{-14}$ erg cm$^{-2}$ s$^{-1}$ in the
energy band $0.2-10$ keV has been obtained from that deep observation allowing
to constrain the putative black hole accretion parameters.
