  A search for single production of doubly-charged Higgs bosons has been
performed using 600.7 pb^-1 of e+e- collision data with sqrt(s)=189--209GeV
collected by the OPAL detector at LEP. No evidence for the existence of H++/--
is observed. Upper limits on the Yukawa coupling of the H++/-- to like-signed
electron pairs are derived. Additionally, indirect constraints on the Yukawa
coupling from Bhabha scattering, where the H++/-- would contribute via
t-channel exchange, are derived for M(H++/--) < 2TeV. These are the first
results for both a single production search and constraints from Bhabha
scattering reported from LEP.
