  Virtual leptoquarks could be detected at HERA through some nonstandard
effects. Here we explore the possibility that virtual leptoquarks could be
discovered via $e u --> e c$ scattering, assuming integrated luminosity of 200
pb$^{-1}$ and charm identification efficiency of 1%. We study the implications
of low energy data for the leptoquarks couplings and find that the most
relevant bound for the HERA cross sections comes from inclusive $c -->
e^+e^-~+~any$. This bound implies that the $e u --> e c$ cross sections for
virtual leptoquarks are just too small for observation of the signal. With an
improvement by a factor of ~2 on the luminosity or on charm identification it
could be possible to see virtual leptoquarks with {\it maximum couplings} up to
~1.5 - 2 TeV. However, the prospects for discovering the virtual particles if
their couplings are somewhat below present bounds are very dim. We point out
that this cross section could be very large for leptoquarks lighter than HERA's
kinematical limit, and if such a leptoquark is discovered we recommend
searching for a possible $e u --> e c$ signal. Our results may also serve as an
update on the maximum cross sections for leptoquark mediated $e u --> \mu c$
scattering.
